draft-ietf-mpls-rsvp-te-p2mp-03.txt   draft-ietf-mpls-rsvp-te-p2mp-04.txt 
Network Working Group R. Aggarwal (Editor) Network Working Group R. Aggarwal (Editor)
Internet Draft Juniper Networks Internet Draft Juniper Networks
Expiration Date: April 2006 Expiration Date: October 2006
D. Papadimitriou (Editor) D. Papadimitriou (Editor)
Alcatel Alcatel
S. Yasukawa (Editor) S. Yasukawa (Editor)
NTT NTT
October 2005 April 2006
Extensions to RSVP-TE for Point to Multipoint TE LSPs Extensions to RSVP-TE for Point to Multipoint TE LSPs
draft-ietf-mpls-rsvp-te-p2mp-03.txt draft-ietf-mpls-rsvp-te-p2mp-04.txt
Status of this Memo Status of this Memo
By submitting this Internet-Draft, each author represents that any By submitting this Internet-Draft, each author represents that any
applicable patent or other IPR claims of which he or she is aware applicable patent or other IPR claims of which he or she is aware
have been or will be disclosed, and any of which he or she becomes have been or will be disclosed, and any of which he or she becomes
aware will be disclosed, in accordance with Section 6 of BCP 79. aware will be disclosed, in accordance with Section 6 of BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
skipping to change at page 3, line 23 skipping to change at page 3, line 23
4.3 Sub-Groups ............................................ 6 4.3 Sub-Groups ............................................ 6
4.4 S2L Sub-LSPs .......................................... 7 4.4 S2L Sub-LSPs .......................................... 7
4.4.1 Representation of a S2L Sub-LSP ....................... 7 4.4.1 Representation of a S2L Sub-LSP ....................... 7
4.4.2 S2L Sub-LSPs and Path Messages ........................ 7 4.4.2 S2L Sub-LSPs and Path Messages ........................ 7
4.5 Explicit Routing ...................................... 8 4.5 Explicit Routing ...................................... 8
5 Path Message .......................................... 10 5 Path Message .......................................... 10
5.1 Path Message Format ................................... 10 5.1 Path Message Format ................................... 10
5.2 Path Message Processing ............................... 11 5.2 Path Message Processing ............................... 11
5.2.1 Multiple Path Messages ................................ 12 5.2.1 Multiple Path Messages ................................ 12
5.2.2 Multiple S2L Sub-LSPs in one Path message ............. 13 5.2.2 Multiple S2L Sub-LSPs in one Path message ............. 13
5.2.3 Transit Fragmentation ................................. 14 5.2.3 Transit Fragmentation ................................. 15
5.2.4 Control of Branch Fate Sharing ........................ 15 5.2.4 Control of Branch Fate Sharing ........................ 15
5.3 Grafting .............................................. 15 5.3 Grafting .............................................. 16
6 Resv Message .......................................... 16 6 Resv Message .......................................... 16
6.1 Resv Message Format ................................... 16 6.1 Resv Message Format ................................... 16
6.2 Resv Message Processing ............................... 17 6.2 Resv Message Processing ............................... 18
6.2.1 Resv Message Throttling ............................... 18 6.2.1 Resv Message Throttling ............................... 19
6.3 Record Routing ........................................ 18 6.3 Record Routing ........................................ 19
6.3.1 RRO Processing ........................................ 18 6.3.1 RRO Processing ........................................ 19
6.4 Reservation Style ..................................... 19 6.4 Reservation Style ..................................... 19
7 PathTear Message ...................................... 19 7 PathTear Message ...................................... 20
7.1 PathTear Message Format ............................... 19 7.1 PathTear Message Format ............................... 20
7.2 Pruning ............................................... 20 7.2 Pruning ............................................... 20
7.2.1 Implicit S2L Sub-LSP Teardown ......................... 20 7.2.1 Implicit S2L Sub-LSP Teardown ......................... 20
7.2.2 Explicit S2L Sub-LSP Teardown ........................ 20 7.2.2 Explicit S2L Sub-LSP Teardown ........................ 21
8 Notify and ResvConf Messages .......................... 21 8 Notify and ResvConf Messages .......................... 21
8.1 Notify Messages ....................................... 21 8.1 Notify Messages ....................................... 21
8.2 ResvConf Messages ..................................... 22 8.2 ResvConf Messages ..................................... 23
9 Refresh Reduction ..................................... 23 9 Refresh Reduction ..................................... 24
10 State Management ...................................... 23 10 State Management ...................................... 24
10.1 Incremental State Update .............................. 23 10.1 Incremental State Update .............................. 24
10.2 Combining Multiple Path Messages ...................... 24 10.2 Combining Multiple Path Messages ...................... 25
11 Error Processing ...................................... 25 11 Error Processing ...................................... 26
11.1 PathErr Messages ...................................... 25 11.1 PathErr Messages ...................................... 26
11.2 ResvErr Messages ...................................... 26 11.2 ResvErr Messages ...................................... 27
11.3 Branch Failure Handling ............................... 26 11.3 Branch Failure Handling ............................... 27
12 Admin Status Change ................................... 27 12 Admin Status Change ................................... 28
13 Label Allocation on LANs with Multiple Downstream Nodes. 28 13 Label Allocation on LANs with Multiple Downstream Nodes ..28
14 P2MP LSP and Sub-LSP Re-optimization .................. 28 14 P2MP LSP and Sub-LSP Re-optimization .................. 29
14.1 Make-before-break ..................................... 28 14.1 Make-before-break ..................................... 29
14.2 Sub-Group Based Re-optimization ....................... 28 14.2 Sub-Group Based Re-optimization ....................... 29
15 Fast Reroute .......................................... 29 15 Fast Reroute .......................................... 30
15.1 Facility Backup ....................................... 29 15.1 Facility Backup ....................................... 30
15.2 One to One Backup ..................................... 30 15.1.1 Link Protection ....................................... 30
16 Support for LSRs that are not P2MP Capable ............ 30 15.1.2 Node Protection ....................................... 31
17 Reduction in Control Plane Processing with LSP Hierarchy. 32 15.2 One to One Backup ..................................... 31
18 P2MP LSP Remerging and Cross-Over ..................... 32 16 Support for LSRs that are not P2MP Capable ............ 32
18.1 Procedures ............................................ 33 17 Reduction in Control Plane Processing with LSP Hierarchy..34
18.1.1 Re-Merge Procedures ................................... 34 18 P2MP LSP Remerging and Cross-Over ..................... 34
19 New and Updated Message Objects ....................... 36 18.1 Procedures ............................................ 35
19.1 SESSION Object ........................................ 36 18.1.1 Re-Merge Procedures ................................... 36
19.1.1 P2MP LSP Tunnel IPv4 SESSION Object ................... 36 19 New and Updated Message Objects ....................... 38
19.1.2 P2MP LSP Tunnel IPv6 SESSION Object ................... 37 19.1 SESSION Object ........................................ 38
19.2 SENDER_TEMPLATE object ................................ 37 19.1.1 P2MP LSP Tunnel IPv4 SESSION Object ................... 38
19.2.1 P2MP LSP Tunnel IPv4 SENDER_TEMPLATE Object ........... 38 19.1.2 P2MP LSP Tunnel IPv6 SESSION Object ................... 39
19.2.2 P2MP LSP Tunnel IPv6 SENDER_TEMPLATE Object ........... 39 19.2 SENDER_TEMPLATE object ................................ 39
19.3 <S2L_SUB_LSP> Object .................................. 40 19.2.1 P2MP LSP Tunnel IPv4 SENDER_TEMPLATE Object ........... 40
19.3.1 <S2L_SUB_LSP> IPv4 Object ............................. 40 19.2.2 P2MP LSP Tunnel IPv6 SENDER_TEMPLATE Object ........... 40
19.3.2 <S2L_SUB_LSP> IPv6 Object ............................. 40 19.3 <S2L_SUB_LSP> Object .................................. 41
19.4 FILTER_SPEC Object .................................... 40 19.3.1 <S2L_SUB_LSP> IPv4 Object ............................. 41
19.4.1 P2MP LSP_IPv4 FILTER_SPEC Object ...................... 41 19.3.2 <S2L_SUB_LSP> IPv6 Object ............................. 42
19.4.2 P2MP LSP_IPv4 FILTER_SPEC Object ...................... 41 19.4 FILTER_SPEC Object .................................... 42
19.5 P2MP SECONDARY_EXPLICIT_ROUTE Object (SERO) ........... 41 19.4.1 P2MP LSP_IPv4 FILTER_SPEC Object ...................... 42
19.6 P2MP SECONDARY_RECORD_ROUTE Object (SRRO) ............. 41 19.4.2 P2MP LSP_IPv4 FILTER_SPEC Object ...................... 42
20 IANA Considerations ................................... 41 19.5 P2MP SECONDARY_EXPLICIT_ROUTE Object (SERO) ........... 43
20.1 New Class Numbers ..................................... 41 19.6 P2MP SECONDARY_RECORD_ROUTE Object (SRRO) ............. 43
20.2 New Class Types ....................................... 42 20 IANA Considerations ................................... 43
20.3 New Error Codes ....................................... 42 20.1 New Class Numbers ..................................... 43
20.4 LSP Attributes Flags .................................. 43 20.2 New Class Types ....................................... 43
21 Security Considerations ............................... 43 20.3 New Error Values ...................................... 44
22 Acknowledgements ...................................... 43 20.4 LSP Attributes Flags .................................. 45
23 Appendix .............................................. 43 21 Security Considerations ............................... 45
23.1 Example ............................................... 43 22 Acknowledgements ...................................... 45
24 References ............................................ 45 23 Appendix .............................................. 45
24.1 Normative References .................................. 45 23.1 Example ............................................... 45
24.2 Informative References ................................ 46 24 References ............................................ 47
25 Author Information .................................... 47 24.1 Normative References .................................. 47
25.1 Editor Information .................................... 47 24.2 Informative References ................................ 48
25.2 Contributor Information ............................... 47 25 Author Information .................................... 49
26 Intellectual Property ................................. 50 25.1 Editor Information .................................... 49
27 Full Copyright Statement .............................. 50 25.2 Contributor Information ............................... 49
28 Acknowledgement ....................................... 51 26 Intellectual Property ................................. 52
27 Full Copyright Statement .............................. 52
28 Acknowledgement ....................................... 53
1. Conventions used in this document 1. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119 [KEYWORDS]. document are to be interpreted as described in RFC-2119 [KEYWORDS].
2. Terminology 2. Terminology
This document uses terminologies defined in [RFC3031], [RFC2205], This document uses terminologies defined in [RFC3031], [RFC2205],
[RFC3209], [RFC3473] and [P2MP-REQ]. [RFC3209], [RFC3473] and [RFC4461].
3. Introduction 3. Introduction
[RFC3209] defines a mechanism for setting up P2P TE LSPs in MPLS [RFC3209] defines a mechanism for setting up P2P TE LSPs in MPLS
networks. [RFC3473] defines extensions to [RFC3209] for setting up P2P networks. [RFC3473] defines extensions to [RFC3209] for setting up
TE LSPs in GMPLS networks. However these specifications do not P2P TE LSPs in GMPLS networks. However these specifications do not
provide a mechanism for building P2MP TE LSPs. provide a mechanism for building P2MP TE LSPs.
This document defines extensions to RSVP-TE protocol [RFC3209, This document defines extensions to the RSVP-TE protocol [RFC3209,
RFC3473] to support P2MP TE LSPs satisfying the set of requirements RFC3473 to support P2MP TE LSPs satisfying the set of requirements
described in [P2MP-REQ]. described in [RFC4461].
This document relies on the semantics of RSVP that RSVP-TE inherits This document relies on the semantics of RSVP that RSVP-TE inherits
for building P2MP LSPs. A P2MP LSP is comprised of multiple S2L for building P2MP LSPs. A P2MP LSP is comprised of multiple S2L sub-
sub-LSPs. These S2L sub-LSPs are set up between the ingress and egress LSPs. These S2L sub-LSPs are set up between the ingress and egress
LSRs and are appropriately combined by the branch LSRs using RSVP LSRs and are appropriately combined by the branch LSRs using RSVP
semantics to result in a P2MP TE LSP. One Path message may signal one semantics to result in a P2MP TE LSP. One Path message may signal one
or multiple S2L sub-LSPs. Hence the S2L sub-LSPs belonging to a P2MP or multiple S2L sub-LSPs. Hence the S2L sub-LSPs belonging to a P2MP
LSP can be signaled using one Path message or split across multiple LSP can be signaled using one Path message or split across multiple
Path messages. Path messages.
Path computation and P2MP application specific aspects are outside of Path computation and P2MP application specific aspects are outside
the scope of this document. the scope of this document.
4. Mechanism 4. Mechanism
This document describes a solution that optimizes data replication by This document describes a solution that optimizes data replication by
allowing non-ingress nodes in the network to be replication/branch allowing non-ingress nodes in the network to be replication/branch
nodes. A branch node is a LSR that is capable of replicating the nodes. A branch node is an LSR that is capable of replicating the
incoming data on two or more outgoing interfaces. The solution relies incoming data on two or more outgoing interfaces. The solution relies
on RSVP-TE in the network for setting up a P2MP TE LSP. on RSVP-TE in the network for setting up a P2MP TE LSP.
The P2MP TE LSP is set up by associating multiple S2L TE sub-LSPs and The P2MP TE LSP is set up by associating multiple S2L sub-LSPs and
relying on data replication at branch nodes. This is described relying on data replication at branch nodes. This is described
further in the following sub-sections by describing P2MP Tunnels and further in the following sub-sections by describing P2MP Tunnels and
how they relate to S2L sub-LSPs. how they relate to S2L sub-LSPs.
4.1. P2MP Tunnels 4.1. P2MP Tunnels
The specific aspect related to P2MP TE LSP is the action required at The specific aspect related to a P2MP TE LSP is the action required
a branch node, where data replication occurs. Incoming MPLS labeled at a branch node, where data replication occurs. Incoming MPLS
data is appropriately replicated to several outgoing interfaces which labeled data is appropriately replicated to several outgoing
may have different labels. interfaces which may have different labels.
A P2MP TE Tunnel comprises of one or more P2MP LSPs. A P2MP TE Tunnel A P2MP TE Tunnel comprises one or more P2MP LSPs. A P2MP TE Tunnel is
is identified by a P2MP SESSION object. This object contains the identified by a P2MP SESSION object. This object contains the
identifier of the P2MP Session which includes the P2MP ID, a tunnel identifier of the P2MP Session which includes the P2MP ID, a tunnel
ID and an extended tunnel ID. ID and an extended tunnel ID.
The fields of a P2MP SESSION object are identical to those of the The fields of a P2MP SESSION object are identical to those of the
SESSION object defined in [RFC3209] except that the Tunnel Endpoint SESSION object defined in [RFC3209] except that the Tunnel Endpoint
Address field is replaced by the P2MP Identifier (P2MP ID) field. Address field is replaced by the P2MP Identifier (P2MP ID) field.
The P2MP ID provides an identifier for the set of destinations of the The P2MP ID provides an identifier for the set of destinations of the
P2MP TE Tunnel. P2MP TE Tunnel.
skipping to change at page 6, line 38 skipping to change at page 6, line 38
ID, and Extended Tunnel ID that are part of the P2MP SESSION object, ID, and Extended Tunnel ID that are part of the P2MP SESSION object,
and the tunnel sender address and LSP ID fields of the P2MP and the tunnel sender address and LSP ID fields of the P2MP
SENDER_TEMPLATE object. The new P2MP SENDER_TEMPLATE object is SENDER_TEMPLATE object. The new P2MP SENDER_TEMPLATE object is
defined in section 20.2. defined in section 20.2.
4.3. Sub-Groups 4.3. Sub-Groups
As with all other RSVP controlled LSPs, P2MP LSP state is managed As with all other RSVP controlled LSPs, P2MP LSP state is managed
using RSVP messages. While use of RSVP messages is the same, P2MP LSP using RSVP messages. While use of RSVP messages is the same, P2MP LSP
state differs from P2P LSP state in a number of ways. The two most state differs from P2P LSP state in a number of ways. The two most
notable differences are that a P2MP LSP comprises multiple S2L notable differences are that a P2MP LSP comprises multiple S2L Sub-
Sub-LSPs and that, as a result of this, it may not be possible to LSPs and that, as a result of this, it may not be possible to
represent full state in a single IP packet and even more likely that it represent full state in a single IP packet and even more likely that
can't fit into a single IP packet. It must also be possible to it can't fit into a single IP packet. It must also be possible to
efficiently add and remove endpoints to and from P2MP TE LSPs. An efficiently add and remove endpoints to and from P2MP TE LSPs. An
additional issue is that P2MP LSP must also handle the state "remerge" additional issue is that the P2MP LSP must also handle the state
problem, see [P2MP-REQ]. "remerge" problem, see [RFC4461].
These differences in P2MP state are addressed through the addition of These differences in P2MP state are addressed through the addition of
a sub-group identifier (Sub-Group ID) and sub-group originator a sub-group identifier (Sub-Group ID) and sub-group originator (Sub-
(Sub-Group Originator ID) to the SENDER_TEMPLATE and FILTER_SPEC Group Originator ID) to the SENDER_TEMPLATE and FILTER_SPEC objects.
objects. Taken together the Sub-Group ID and Sub-Group Originator ID
are referred to as the Sub-Group fields. Taken together the Sub-Group ID and Sub-Group Originator ID are
referred to as the Sub-Group fields.
The Sub-Group fields, together with rest of the SENDER_TEMPLATE and The Sub-Group fields, together with rest of the SENDER_TEMPLATE and
SESSION objects, are used to represent a portion of a P2MP LSP's SESSION objects, are used to represent a portion of a P2MP LSP's
state. This portion of a P2MP LSP's state refers only to signaling state. This portion of a P2MP LSP's state refers only to signaling
state and not data plane replication or branching. For example, it is state and not data plane replication or branching. For example, it is
possible for a node to "branch" signaling state for a P2MP LSP, but possible for a node to "branch" signaling state for a P2MP LSP, but
to not branch the data associated with the P2MP LSP. Typical to not branch the data associated with the P2MP LSP. Typical
applications for generation and use of multiple subgroups are adding applications for generation and use of multiple subgroups are adding
an egress and semantic fragmentation to ensure that a Path message an egress and semantic fragmentation to ensure that a Path message
remains within a single IP packet. remains within a single IP packet.
4.4. S2L Sub-LSPs 4.4. S2L Sub-LSPs
A P2MP LSP is constituted of one or more S2L sub-LSPs. A P2MP LSP is constituted of one or more S2L sub-LSPs.
4.4.1. Representation of a S2L Sub-LSP 4.4.1. Representation of a S2L Sub-LSP
A S2L sub-LSP exists within the context of a P2MP LSP. Thus it is An S2L sub-LSP exists within the context of a P2MP LSP. Thus it is
identified by the P2MP ID, Tunnel ID, and Extended Tunnel ID that are identified by the P2MP ID, Tunnel ID, and Extended Tunnel ID that are
part of the P2MP SESSION, the tunnel sender address and LSP ID fields part of the P2MP SESSION, the tunnel sender address and LSP ID fields
of the P2MP SENDER_TEMPLATE object, and the S2L sub-LSP destination of the P2MP SENDER_TEMPLATE object, and the S2L sub-LSP destination
address that is part of the <S2L_SUB_LSP> object. The <S2L_SUB_LSP> address that is part of the <S2L_SUB_LSP> object. The <S2L_SUB_LSP>
object is defined in section 20.3. object is defined in section 20.3.
An EXPLICIT_ROUTE Object (ERO) or P2MP SECONDARY_EXPLICIT_ROUTE An EXPLICIT_ROUTE Object (ERO) or P2MP SECONDARY_EXPLICIT_ROUTE
Object (SERO) is used to optionally specify the explicit route of a Object (SERO) is used to optionally specify the explicit route of a
S2L sub-LSP. Each ERO or a SERO that is signaled corresponds to a S2L sub-LSP. Each ERO or SERO that is signaled corresponds to a
particular <S2L_SUB_LSP> object. Details of explicit route encoding particular <S2L_SUB_LSP> object. Details of explicit route encoding
are specified in section 4.5. The SECONDARY_EXPLICIT_ROUTE Object is are specified in section 4.5. The SECONDARY_EXPLICIT_ROUTE Object is
defined in [RECOVERY], a new P2MP SECONDARY_EXPLICIT_ROUTE Object C- defined in [RECOVERY], a new P2MP SECONDARY_EXPLICIT_ROUTE Object C-
C-type is defined in Section 20.5 and a matching P2MP type is defined in Section 20.5 and a matching P2MP
SECONDARY_RECORD_ROUTE Object C-type is defined in Section 20.6. SECONDARY_RECORD_ROUTE Object C-type is defined in Section 20.6.
4.4.2. S2L Sub-LSPs and Path Messages 4.4.2. S2L Sub-LSPs and Path Messages
The mechanism in this document allows a P2MP LSP to be signaled using The mechanism in this document allows a P2MP LSP to be signaled using
one or more Path messages. Each Path message may signal one or more one or more Path messages. Each Path message may signal one or more
S2L sub-LSPs. Support for multiple Path messages is desirable as one S2L sub-LSPs. Support for multiple Path messages is desirable as one
Path message may not be large enough to fit all the S2L sub-LSPs; and Path message may not be large enough to contain all the S2L sub-LSPs;
they also allow separate manipulation of sub-trees of the P2MP LSP. and they also allow separate manipulation of sub-trees of the P2MP
The reason for allowing a single Path message, to signal multiple S2L LSP. The reason for allowing a single Path message, to signal
sub-LSPs, is to optimize the number of control messages needed to multiple S2L sub-LSPs, is to optimize the number of control messages
setup a P2MP LSP. needed to setup a P2MP LSP.
4.5. Explicit Routing 4.5. Explicit Routing
When a Path message signals a single S2L sub-LSP (that is, the Path When a Path message signals a single S2L sub-LSP (that is, the Path
message is only targeting a single leaf in the P2MP tree), the message is only targeting a single leaf in the P2MP tree), the
EXPLICIT_ROUTE object encodes the path from the ingress LSR to the EXPLICIT_ROUTE object encodes the path from the ingress LSR to the
egress LSR. The Path message also includes the <S2L_SUB_LSP> object egress LSR. The Path message also includes the <S2L_SUB_LSP> object
for the S2L sub-LSP being signaled. The < [<EXPLICIT_ROUTE>], for the S2L sub-LSP being signaled. The < [<EXPLICIT_ROUTE>],
<S2L_SUB_LSP> > tuple represents the S2L sub-LSP and is referred to <S2L_SUB_LSP> > tuple represents the S2L sub-LSP and is referred to
as the sub-LSP descriptor. The absence of the ERO should be as the sub-LSP descriptor. The absence of the ERO should be
interpreted as requiring hop-by-hop routing for the sub-LSP based on interpreted as requiring hop-by-hop routing for the sub-LSP based on
the S2L sub-LSP destination address field of the <S2L_SUB_LSP> object. the S2L sub-LSP destination address field of the <S2L_SUB_LSP>
object.
When a Path message signals multiple S2L sub-LSPs the path of the When a Path message signals multiple S2L sub-LSPs the path of the
first S2L sub-LSP, from the ingress LSR to the egress LSR, is encoded first S2L sub-LSP, from the ingress LSR to the egress LSR, is encoded
in the ERO. The first S2L sub-LSP is the one that corresponds to the in the ERO. The first S2L sub-LSP is the one that corresponds to the
first <S2L_SUB_LSP> object in the Path message. The S2L sub-LSPs first <S2L_SUB_LSP> object in the Path message. The S2L sub-LSPs
coresponding to the <S2L_SUB_LSP> objects that follow are termed as corresponding to the <S2L_SUB_LSP> objects that follow are termed as
subsequent S2L sub-LSPs. In order to avoid the potential repetition subsequent S2L sub-LSPs.
of path information for the parts of S2L sub-LSPs that share hops,
this information is deduced from the explicit routes of other S2L
sub-LSPs using explicit route compression in SEROs.
The path of each subsequent S2L sub-LSP is encoded in a P2MP The path of each subsequent S2L sub-LSP is encoded in a P2MP
SECONDARY_EXPLICIT_ROUTE object (SERO). The format of the SERO is the SECONDARY_EXPLICIT_ROUTE object (SERO). The format of the SERO is the
same as an ERO (as defined in [RFC3209]). Each subsequent S2L sub-LSP same as an ERO (as defined in [RFC3209]). Each subsequent S2L sub-LSP
is represented by tuples of the form < [<P2MP SEC- is represented by tuples of the form < [<P2MP
ONDARY_EXPLICIT_ROUTE>] <S2L_SUB_LSP> >. There is a one to one SECONDARY_EXPLICIT_ROUTE>] <S2L_SUB_LSP> >. An SERO for a particular
correspondence between a <S2L_SUB_LSP> object and a SERO. A SERO for a S2L sub-LSP includes only the path from a certain branch LSR to the
particular S2L sub-LSP includes only the path from a certain branch egress LSR if the path to that branch LSR can be derived from the ERO
LSR to the egress LSR if the path to that branch LSR can be derived or other SEROs. The absence of an SERO should be interpreted as
from the ERO or other SEROs. The absence of a SERO should be requiring hop-by-hop routing for that S2L sub-LSP. Note that the
interpreted as requiring hop-by-hop routing for that S2L sub-LSP. Note destination address is carried in the S2L sub-LSP object. The
that the destination address is carried in the S2L sub-LSP object. encoding of the SERO and <S2L_SUB_LSP> object are described in detail
The encoding of the SERO and <S2L_SUB_LSP> object are described in in section 20.
detail in section 20.
In order to avoid the potential repetition of path information for
the parts of S2L sub-LSPs that share hops, this information is
deduced from the explicit routes of other S2L sub-LSPs using explicit
route compression in SEROs.
Explicit route compression is illustrated using the following figure. Explicit route compression is illustrated using the following figure.
A A
| |
| |
B B
| |
| |
C----D----E C----D----E
skipping to change at page 9, line 17 skipping to change at page 9, line 19
J K L M J K L M
| | | | | | | |
| | | | | | | |
N O P Q--R N O P Q--R
Figure 1. Explicit Route Compression Figure 1. Explicit Route Compression
Figure 1. shows a P2MP LSP with LSR A as the ingress LSR and six Figure 1. shows a P2MP LSP with LSR A as the ingress LSR and six
egress LSRs: (F, N, O, P, Q and R). When all the six S2L sub-LSPs are egress LSRs: (F, N, O, P, Q and R). When all the six S2L sub-LSPs are
signaled in one Path message let us assume that the S2L sub-LSP to signaled in one Path message let us assume that the S2L sub-LSP to
LSR F is the first S2L sub-LSP and the rest are subsequent S2L LSR F is the first S2L sub-LSP and the rest are subsequent S2L sub-
sub-LSPs. Following is one way for the ingress LSR A to encode the S2L LSPs. Following is one way for the ingress LSR A to encode the S2L
sub-LSP explicit routes using compression: sub-LSP explicit routes using compression:
S2L sub-LSP-F: ERO = {B, E, D, C, F}, <S2L_SUB_LSP> object-F S2L sub-LSP-F: ERO = {B, E, D, C, F}, <S2L_SUB_LSP> object-F
S2L sub-LSP-N: SERO = {D, G, J, N}, <S2L_SUB_LSP> object-N S2L sub-LSP-N: SERO = {D, G, J, N}, <S2L_SUB_LSP> object-N
S2L sub-LSP-O: SERO = {E, H, K, O}, <S2L_SUB_LSP> object-O S2L sub-LSP-O: SERO = {E, H, K, O}, <S2L_SUB_LSP> object-O
S2L sub-LSP-P: SERO = {H, L, P}, <S2L_SUB_LSP> object-P, S2L sub-LSP-P: SERO = {H, L, P}, <S2L_SUB_LSP> object-P,
S2L sub-LSP-Q: SERO = {H, I, M, Q}, <S2L_SUB_LSP> object-Q, S2L sub-LSP-Q: SERO = {H, I, M, Q}, <S2L_SUB_LSP> object-Q,
S2L sub-LSP-R: SERO = {Q, R}, <S2L_SUB_LSP> object-R, S2L sub-LSP-R: SERO = {Q, R}, <S2L_SUB_LSP> object-R,
After LSR E processes the incoming Path message from LSR B it sends a After LSR E processes the incoming Path message from LSR B it sends a
skipping to change at page 11, line 4 skipping to change at page 11, line 6
[ <EXPLICIT_ROUTE> ] [ <EXPLICIT_ROUTE> ]
<LABEL_REQUEST> <LABEL_REQUEST>
[ <PROTECTION> ] [ <PROTECTION> ]
[ <LABEL_SET> ... ] [ <LABEL_SET> ... ]
[ <SESSION_ATTRIBUTE> ] [ <SESSION_ATTRIBUTE> ]
[ <NOTIFY_REQUEST> ] [ <NOTIFY_REQUEST> ]
[ <ADMIN_STATUS> ] [ <ADMIN_STATUS> ]
[ <POLICY_DATA> ... ] [ <POLICY_DATA> ... ]
<sender descriptor> <sender descriptor>
[<S2L sub-LSP descriptor list>] [<S2L sub-LSP descriptor list>]
Following is the format of the S2L sub-LSP descriptor list. Following is the format of the S2L sub-LSP descriptor list.
<S2L sub-LSP descriptor list> ::= <S2L sub-LSP descriptor> <S2L sub-LSP descriptor list> ::= <S2L sub-LSP descriptor>
[ <S2L sub-LSP descriptor list> ] [ <S2L sub-LSP descriptor list> ]
<S2L sub-LSP descriptor> ::= <S2L_SUB_LSP> [ <P2MP SEC- <S2L sub-LSP descriptor> ::= <S2L_SUB_LSP> [ <P2MP
ONDARY_EXPLICIT_ROUTE> ] SECONDARY_EXPLICIT_ROUTE> ]
Each LSR MUST use the common objects in the Path message and the S2L Each LSR MUST use the common objects in the Path message and the S2L
sub-LSP descriptors to process each S2L sub-LSP represented by the sub-LSP descriptors to process each S2L sub-LSP represented by the
<S2L_SUB_LSP> object and the SECONDARY-/EXPLICIT_ROUTE object <S2L_SUB_LSP> object and the SECONDARY-/EXPLICIT_ROUTE object
combination. combination.
The first <S2L_SUB_LSP> object's explicit route is specified by the The first <S2L_SUB_LSP> object's explicit route is specified by the
ERO. Explicit routes of subsequent S2L sub-LSPs are specified by the ERO. Explicit routes of subsequent S2L sub-LSPs are specified by the
corresponding SERO. A SERO corresponds to the following <S2L_SUB_LSP> corresponding SERO. A SERO corresponds to the following <S2L_SUB_LSP>
object. object.
The RRO in the sender descriptor contains the hops traversed by the The RRO in the sender descriptor contains the hops traversed by the
Path message and applies to all the S2L sub-LSPs signaled in the Path Path message and applies to all the S2L sub-LSPs signaled in the Path
message. message.
Path message processing is described in the next section. Path message processing is described in the next section.
5.2. Path Message Processing 5.2. Path Message Processing
The ingress-LSR initiates the set up of a S2L sub-LSP to each egress The ingress-LSR initiates the set up of an S2L sub-LSP to each
LSR that is the destination of the P2MP LSP. Each S2L sub-LSP is egress-LSR that is the destination of the P2MP LSP. Each S2L sub-LSP
associated with the same P2MP LSP using common P2MP SESSION object is associated with the same P2MP LSP using common P2MP SESSION object
and <Sender Address, LSP-ID> fields in the P2MP SENDER_TEMPLATE and <Sender Address, LSP-ID> fields in the P2MP SENDER_TEMPLATE
object. Hence it can be combined with other S2L sub-LSPs to form a object. Hence it can be combined with other S2L sub-LSPs to form a
P2MP LSP. Another S2L sub-LSP belonging to the same instance of this P2MP LSP. Another S2L sub-LSP belonging to the same instance of this
S2L sub-LSP (i.e. the same P2MP LSP) shares resources with this S2L S2L sub-LSP (i.e. the same P2MP LSP) shares resources with this S2L
sub-LSP. The session corresponding to the P2MP TE tunnel is sub-LSP. The session corresponding to the P2MP TE tunnel is
determined based on the P2MP SESSION object. Each S2L sub-LSP is determined based on the P2MP SESSION object. Each S2L sub-LSP is
identified using the <S2L_SUB_LSP> object. Explicit routing for the S2L identified using the <S2L_SUB_LSP> object. Explicit routing for the
sub-LSPs is achieved using the ERO and SEROs. S2L sub-LSPs is achieved using the ERO and SEROs.
As mentioned earlier, it is possible to signal S2L sub-LSPs for a As mentioned earlier, it is possible to signal S2L sub-LSPs for a
given P2MP LSP in one or more Path messages. And a given Path message given P2MP LSP in one or more Path messages and a given Path message
can contain one or more S2L sub-LSPs. A LSR that supports RSVP-TE can contain one or more S2L sub-LSPs. A LSR that supports RSVP-TE
signaled P2MP LSPs MUST be able to receive and process multiple Path signaled P2MP LSPs MUST be able to receive and process multiple Path
messages for the same P2MP LSP and multiple S2L sub-LSPs in one Path messages for the same P2MP LSP and multiple S2L sub-LSPs in one Path
message. This implies that a LSR MUST be able to receive and process message. This implies that such an LSR MUST be able to receive and
all objects listed in section 20. process all objects listed in section 20.
5.2.1. Multiple Path Messages 5.2.1. Multiple Path Messages
As described in section 3, either the <EXPLICIT_ROUTE> <S2L_SUB_LSP> As described in section 3, either the <EXPLICIT_ROUTE> <S2L_SUB_LSP>
or the <P2MP SECONDARY_EXPLICIT_ROUTE> <S2L_SUB_LSP> tuple is used to or the <P2MP SECONDARY_EXPLICIT_ROUTE> <S2L_SUB_LSP> tuple is used to
specify a S2L sub-LSP. Multiple Path messages can be used to signal a specify a S2L sub-LSP. Multiple Path messages can be used to signal a
P2MP LSP. Each Path message can signal one or more S2L sub-LSPs. If a P2MP LSP. Each Path message can signal one or more S2L sub-LSPs. If a
Path message contains only one S2L sub-LSP, each LSR along the S2L Path message contains only one S2L sub-LSP, each LSR along the S2L
sub-LSP follows [RFC3209] procedures for processing the Path message sub-LSP follows [RFC3209] procedures for processing the Path message
besides the <S2L_SUB_LSP> object processing described in this docu- besides the <S2L_SUB_LSP> object processing described in this
ment. document.
Processing of Path messages containing more than one S2L sub-LSP is Processing of Path messages containing more than one S2L sub-LSP is
described in Section 5.2.2. described in Section 5.2.2.
An ingress LSR may use multiple Path messages for signaling a P2MP An ingress LSR may use multiple Path messages for signaling a P2MP
LSP. This may be because a single Path message may not be large LSP. This may be because a single Path message may not be large
enough to signal the P2MP LSP. Or it may be while adding leaves to enough to signal the P2MP LSP. Or it may be while adding leaves to
the P2MP LSP the new leaves are signaled in a new Path message. Or an the P2MP LSP the new leaves are signaled in a new Path message. Or an
ingress LSR MAY choose to break the P2MP tree into separate ingress LSR MAY choose to break the P2MP tree into separate
manageable P2MP trees. These trees share the same root and may share the manageable P2MP trees. These trees share the same root and may share
trunk and certain branches. The scope of this management the trunk and certain branches. The scope of this management
decomposition of P2MP trees is bounded by a single tree (the P2MP Tree) decomposition of P2MP trees is bounded by a single tree (the P2MP
and multiple trees with a single leaf each (S2L sub-LSPs). Per Tree) and multiple trees with a single leaf each (S2L sub-LSPs). Per
[P2MP-REQ], a P2MP LSP MUST have consistent attributes across all [RFC4461], a P2MP LSP MUST have consistent attributes across all
portions of a tree. This implies that each Path message that is used portions of a tree. This implies that each Path message that is used
to signal a P2MP LSP is signaled using the same signaling attributes to signal a P2MP LSP is signaled using the same signaling attributes
with the exception of the S2L sub-LSP information. with the exception of the S2L sub-LSP information and Sub-Group
identifiers.
The resulting sub-LSPs from the different Path messages belonging to The resulting sub-LSPs from the different Path messages belonging to
the same P2MP LSP SHOULD share labels and resources where they share the same P2MP LSP SHOULD share labels and resources where they share
hops to prevent multiple copies of the data being sent. hops to prevent multiple copies of the data being sent.
In certain cases a transit LSR may need to generate multiple Path In certain cases a transit LSR may need to generate multiple Path
messages to signal state corresponding to a single received Path messages to signal state corresponding to a single received Path
message. For instance ERO expansion may result in an overflow of the message. For instance ERO expansion may result in an overflow of the
resultant Path message. In this case the message can be decomposed resultant Path message. In this case the message can be decomposed
into multiple Path messages such that each of the messages carry a into multiple Path messages such that each of the messages carry a
subset of the X2L sub-tree carried by the incoming message. subset of the X2L sub-tree carried by the incoming message.
Multiple Path messages generated by a LSR that signal state for the Multiple Path messages generated by an LSR that signal state for the
same P2MP LSP are signaled with the same SESSION object and have the same P2MP LSP are signaled with the same SESSION object and have the
same <Source address, LSP-ID> in the SENDER_TEMPLATE object. In order same <Source address, LSP-ID> in the SENDER_TEMPLATE object. In order
to disambiguate these Path messages a <Sub-Group Originator ID, to disambiguate these Path messages a <Sub-Group Originator ID, sub-
sub-Group ID> tuple is introduced (also referred to as the Sub-Group Group ID> tuple is introduced (also referred to as the Sub-Group
field) and encoded in the SENDER_TEMPLATE object. Multiple Path field) and encoded in the SENDER_TEMPLATE object. Multiple Path
messages generated by a LSR to signal state for the same P2MP LSP messages generated by a LSR to signal state for the same P2MP LSP
have the same Sub-Group Originator ID and have a different sub-Group have the same Sub-Group Originator ID and have a different sub-Group
ID. The Sub-Group Originator ID SHOULD be set to the TE Router ID of ID. The Sub-Group Originator ID MUST be set to the TE Router ID of
the LSR that originates the Path message. This is either the ingress the LSR that originates the Path message. This is either the ingress
LSR or a LSR which re-originates the Path message with its own Sub-Group LSR or a LSR which re-originates the Path message with its own Sub-
Originator ID. Cases when a transit LSR may change the Sub-Group Group Originator ID. Cases when a transit LSR may change the Sub-
Originator ID of an incoming Path message are described below. The Group Originator ID of an incoming Path message are described below.
<Sub-Group Originator ID, sub-Group ID> tuple is globally unique. The The <Sub-Group Originator ID, sub-Group ID> tuple is globally unique.
sub-Group ID space is specific to the Sub-Group Originator ID. The sub-Group ID space is specific to the Sub-Group Originator ID.
Therefore the combination <Sub-Group Originator ID, sub-Group ID> is Therefore the combination <Sub-Group Originator ID, sub-Group ID> is
network-wide unique. Also, a router that changes the Sub-Group network-wide unique. Also, a router that changes the Sub-Group
originator ID of an incoming Path message MUST use the same value of originator ID of an incoming Path message MUST use the same value of
the Sub-Group Originator ID for all outgoing Path messages, for a the Sub-Group Originator ID for all outgoing Path messages, for a
particular P2MP LSP, and SHOULD not vary it during the life of the particular P2MP LSP, and SHOULD not vary it during the life of the
P2MP LSP. P2MP LSP.
5.2.2. Multiple S2L Sub-LSPs in one Path message 5.2.2. Multiple S2L Sub-LSPs in one Path message
The S2L sub-LSP descriptor list allows the signaling of one or more The S2L sub-LSP descriptor list allows the signaling of one or more
S2L sub-LSPs in one Path message. It is possible to signal multiple S2L sub-LSPs in one Path message. It is possible to signal multiple
<S2L_SUB_LSP> object and ERO/SERO combinations in a single Path mes- <S2L_SUB_LSP> object and ERO/SERO combinations in a single Path
sage. Note that these two objects are the ones that differentiate a message. Note that these two objects differentiate a S2L sub-LSP.
S2L sub-LSP.
All LSRs MUST process the ERO corresponding to the first S2L sub-LSP All LSRs MUST process the ERO corresponding to the first S2L sub-LSP
when the ERO is present. If one or more SEROs are present an ERO MUST if the ERO is present. If one or more SEROs are present an ERO MUST
be present. The first S2L sub-LSP MUST be propagated in a Path be present. The first S2L sub-LSP MUST be propagated in a Path
message by each LSR along the explicit route specified by the ERO. A message by each LSR along the explicit route specified by the ERO, if
LSR MUST process a S2L sub-LSP descriptor for a subsequent S2L sub-LSP the ERO is present. Else it MUST be propagated using hop-by-hop
only if the first hop in the corresponding SERO is a local address of routing towards the destination identified by the <S2L_SUB_LSP>
that LSR. If this is not the case the S2L sub-LSP descriptor MUST be object.
included in the Path message sent to LSR that is the next hop to
reach the first hop in the SERO. This next hop is determined by using A LSR MUST process a S2L sub-LSP descriptor for a subsequent S2L sub-
the ERO or other SEROs that encode the path to the SERO's first hop. LSP as follows:
If this is the case and the LSR is also the egress, the S2L sub-LSP
descriptor MUST NOT be propagated downstream. If this is the case and If the <S2L_SUB_LSP> object is followed by an SERO, the LSR MUST check
the LSR is not the egress the S2L sub-LSP descriptor MUST be included the first hop in the SERO:
in a Path message sent to the next-hop determined from the SERO. - If the first hop of the SERO identifies a local address of the
LSR, and the LSR is also the egress identified by the
<S2L_SUB_LSP> object, the descriptor MUST NOT be propagated
downstream, but the SERO may be used for egress control per
[RFC4003].
- If the first hop of the SERO identifies a local address of the
LSR, and the LSR is not the egress as identified by the
<S2L_SUB_LSP> object the S2L sub-LSP descriptor MUST be
included in a Path message sent to the next-hop determined
from the SERO.
- If the first hop of the SERO is not a local address of the LSR
the S2L sub-LSP descriptor MUST be included in the Path message
sent to LSR that is the next hop to reach the first hop in the
SERO. This next hop is determined by using the ERO or other
SEROs that encode the path to the SERO's first hop.
If the <S2L_SUB_LSP> object is not followed by an SERO, the LSR MUST
examine the <S2L_SUB_LSP> object:
- If this LSR is the egress as identified by the <S2L_SUB_LSP>
object, the S2L sub-LSP descriptor MUST NOT be propagated
downstream.
- If this LSR is not the egress as identified by the <S2L_SUB_LSP>
object, the LSR MUST make a routing decision to determine the
next hop towards the egress, and MUST include the S2L sub-LSP
descriptor in a Path message sent to the next-hop towards the
egress. In this case, the LSR MAY insert an SERO into the
S2L sub-LSP descriptor.
Hence a branch LSR MUST only propagate the relevant S2L sub-LSP Hence a branch LSR MUST only propagate the relevant S2L sub-LSP
descriptors on each downstream link. A S2L sub-LSP descriptor list descriptors on each downstream link. A S2L sub-LSP descriptor list
that is propagated on a downstream link MUST only contain those S2L that is propagated on a downstream link MUST only contain those S2L
sub-LSPs that are routed using that link. This processing MAY result sub-LSPs that are routed using that link. This processing MAY result
in a subsequent S2L sub-LSP in an incoming Path message to become the in a subsequent S2L sub-LSP in an incoming Path message to become the
first S2L sub-LSP in an outgoing Path message. first S2L sub-LSP in an outgoing Path message.
Note that if one or more SEROs contain loose hops, expansion of such Note that if one or more SEROs contain loose hops, expansion of such
loose hops MAY result in overflowing the Path message size. Section loose hops MAY result in overflowing the Path message size. Section
5.2.3 describes how signaling of the set of S2L sub-LSPs can be split 5.2.3 describes how signaling of the set of S2L sub-LSPs can be split
in more than one Path message. in more than one Path message.
The RECORD_ROUTE Object (RRO) contains the hops traversed by the Path The RECORD_ROUTE Object (RRO) contains the hops traversed by the Path
message and applies to all the S2L sub-LSPs signaled in the path message and applies to all the S2L sub-LSPs signaled in the Path
message. A transit LSR MUST append its address in an incoming RRO and message. A transit LSR MUST append its address in an incoming RRO and
propagate it downstream. A branch LSR MUST form a new RRO for each of propagate it downstream. A branch LSR MUST form a new RRO for each of
the outgoing Path messages. Each such updated RRO MUST be formed the outgoing Path messages by copying the RRO from the incoming Path
using the rules in [RFC3209]. message and appending its address. Each such updated RRO MUST be
formed using the rules in [RFC3209].
If a LSR is unable to support a S2L sub-LSP in a Path message, a If a LSR is unable to support a S2L sub-LSP in a Path message, a
PathErr message MUST be sent for the impacted S2L sub-LSP, and normal PathErr message MUST be sent for the impacted S2L sub-LSP, and normal
processing of the rest of the P2MP LSP SHOULD continue. The default processing of the rest of the P2MP LSP SHOULD continue. The default
behavior is that the remainder of the LSP is not impacted (that is, behavior is that the remainder of the LSP is not impacted (that is,
all other branches are allowed to set up) and the failed branches are all other branches are allowed to set up) and the failed branches are
reported in PathErr messages in which the Path_State_Removed flag reported in PathErr messages in which the Path_State_Removed flag
MUST NOT be set. However, the ingress LSR may set a LSP Integrity MUST NOT be set. However, the ingress LSR may set a LSP Integrity
flag to request that if there is a setup failure on any branch the flag to request that if there is a setup failure on any branch the
entire LSP should fail to set up. This is described further in entire LSP should fail to set up. This is described further in
section 12. section 12.
5.2.3. Transit Fragmentation 5.2.3. Transit Fragmentation
In certain cases a transit LSR may need to generate multiple Path In certain cases a transit LSR may need to generate multiple Path
messages to signal state corresponding to a single received Path messages to signal state corresponding to a single received Path
message. For instance ERO expansion may result in an overflow of the message. For instance ERO expansion may result in an overflow of the
resultant Path message. It is desirable not to rely on IP resultant Path message. It is desirable not to rely on IP
fragmentation in this case. In order to achieve this, the multiple Path fragmentation in this case. In order to achieve this, the multiple
messages generated by the transit LSR, are signaled with the Sub-Group Path messages generated by the transit LSR, are signaled with the
Originator ID set to the TE Router ID of the transit LSR and a dis- Sub-Group Originator ID set to the TE Router ID of the transit LSR
tinct sub-Group ID. Thus each distinct Path message that is generated and a distinct sub-Group ID for each Path message. Thus each distinct
by the transit LSR for the P2MP LSP carries a distinct <Sub-Group Path message that is generated by the transit LSR for the P2MP LSP
Originator ID, Sub-Group ID> tuple. carries a distinct <Sub-Group Originator ID, Sub-Group ID> tuple.
When multiple Path messages are used by an ingress or transit node, When multiple Path messages are used by an ingress or transit node,
each Path message SHOULD be identical with the exception of the S2L each Path message SHOULD be identical with the exception of the S2L
sub-LSP related information (e.g., SERO), message and hop information sub-LSP related information (e.g., SERO), message and hop information
(e.g., INTEGRITY, MESSAGE_ID and RSVP_HOP), and the sub-group fields (e.g., INTEGRITY, MESSAGE_ID and RSVP_HOP), and the sub-group fields
of the SENDER_TEMPLATE objects. Except when performing a make- of the SENDER_TEMPLATE objects. Except when performing a make-
before-break operation as specified in section 14.1, the tunnel before-break operation as specified in section 14.1, the tunnel
sender address and LSP ID fields MUST be the same in each message, sender address and LSP ID fields MUST be the same in each message,
and for transit nodes, the same as the values in the received Path and for transit nodes, the same as the values in the received Path
message. message.
skipping to change at page 15, line 20 skipping to change at page 16, line 6
failure during LSP setup or after an LSP has been established. The failure during LSP setup or after an LSP has been established. The
default behavior is that only the branches downstream of the failure default behavior is that only the branches downstream of the failure
are not established, but the ingress may request 'LSP integrity' such are not established, but the ingress may request 'LSP integrity' such
that any failure anywhere within the LSP tree causes the entire P2MP that any failure anywhere within the LSP tree causes the entire P2MP
LSP to fail. LSP to fail.
The ingress LSP may request 'LSP integrity' by setting bit [TBA] of The ingress LSP may request 'LSP integrity' by setting bit [TBA] of
the Attributes Flags TLV. The bit is set if LSP integrity is the Attributes Flags TLV. The bit is set if LSP integrity is
required. required.
It is RECOMMENDED to use the LSP_ATTRIBUTES Object for this flag and It is RECOMMENDED to use the LSP_REQUIRED_ATTRIBUTES Object.
not the LSP_REQUIRED_ATTRIBUTES Object.
A branch LSR that supports the Attributes Flags TLV and recognizes A branch LSR that supports the Attributes Flags TLV and recognizes
this bit MUST support LSP integrity or reject the LSP setup with a this bit MUST support LSP integrity or reject the LSP setup with a
PathErr message carrying the error "Routing Error"/"Unsupported LSP PathErr message carrying the error "Routing Error"/"Unsupported LSP
Integrity" Integrity"
5.3. Grafting 5.3. Grafting
The operation of adding egress LSR(s) to an existing P2MP LSP is The operation of adding egress LSR(s) to an existing P2MP LSP is
termed as grafting. This operation allows egress nodes to join a P2MP termed as grafting. This operation allows egress nodes to join a P2MP
skipping to change at page 15, line 43 skipping to change at page 16, line 28
There are two methods to add S2L sub-LSPs to a P2MP LSP. The first There are two methods to add S2L sub-LSPs to a P2MP LSP. The first
is to add new S2L sub-LSPs to the P2MP LSP by adding them to an is to add new S2L sub-LSPs to the P2MP LSP by adding them to an
existing Path message and refreshing the entire Path message. Path existing Path message and refreshing the entire Path message. Path
message processing described in section 4 results in adding these S2L message processing described in section 4 results in adding these S2L
sub-LSPs to the P2MP LSP. Note that as a result of adding one or more sub-LSPs to the P2MP LSP. Note that as a result of adding one or more
S2L sub-LSPs to a Path message the ERO compression encoding may have S2L sub-LSPs to a Path message the ERO compression encoding may have
to be recomputed. to be recomputed.
The second is to use incremental updates described in section 10.1. The second is to use incremental updates described in section 10.1.
The egress LSRs can be added by signaling only the impacted S2L The egress LSRs can be added by signaling only the impacted S2L sub-
sub-LSPs in a new Path message. Hence other S2L sub-LSPs do not have LSPs in a new Path message. Hence other S2L sub-LSPs do not have to
to be re-signaled. be re-signaled.
6. Resv Message 6. Resv Message
6.1. Resv Message Format 6.1. Resv Message Format
The Resv message follows the [RFC3209] and [RFC3473] format: The Resv message follows the [RFC3209] and [RFC3473] format:
<Resv Message> ::= <Common Header> [ <INTEGRITY> ] <Resv Message> ::= <Common Header> [ <INTEGRITY> ]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ] [ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ] [ <MESSAGE_ID> ]
skipping to change at page 17, line 4 skipping to change at page 17, line 31
list> ] list> ]
<SE filter spec> ::= <FILTER_SPEC> <LABEL> [ <RECORD_ROUTE> ] <SE filter spec> ::= <FILTER_SPEC> <LABEL> [ <RECORD_ROUTE> ]
[ <S2L sub-LSP descriptor list> ] [ <S2L sub-LSP descriptor list> ]
<S2L sub-LSP descriptor list> ::= <S2L sub-LSP descriptor> <S2L sub-LSP descriptor list> ::= <S2L sub-LSP descriptor>
[ <S2L sub-LSP descriptor list> ] [ <S2L sub-LSP descriptor list> ]
<S2L sub-LSP descriptor> ::= <S2L_SUB_LSP> [ <P2MP <S2L sub-LSP descriptor> ::= <S2L_SUB_LSP> [ <P2MP
SECONDARY_EXPLICIT_ROUTE> ] SECONDARY_EXPLICIT_ROUTE> ]
FILTER_SPEC is defined in section 20.4. FILTER_SPEC is defined in section 20.4.
The S2L sub-LSP descriptor has the same format as in section 4.1 with The S2L sub-LSP descriptor has the same format as in section 4.1 with
the difference that a P2MP_SECONDARY_RECORD_ROUTE object is used in the difference that a P2MP_SECONDARY_RECORD_ROUTE object is used in
place of a P2MP SECONDARY_EXPLICIT_ROUTE object. The P2MP_SEC- place of a P2MP SECONDARY_EXPLICIT_ROUTE object. The
ONDARY_RECORD_ROUTE objects follow the same compression mechanism as P2MP_SECONDARY_RECORD_ROUTE objects follow the same compression
the P2MP SECONDARY_EXPLICIT_ROUTE objects. Note that that a Resv mechanism as the P2MP SECONDARY_EXPLICIT_ROUTE objects. Note that
message can signal multiple S2L sub-LSPs that may belong to the same that a Resv message can signal multiple S2L sub-LSPs that may belong
FILTER_SPEC object or different FILTER_SPEC objects. The same label to the same FILTER_SPEC object or different FILTER_SPEC objects. The
SHOULD be allocated if the <Sender Address, LSP-ID> fields of the same label SHOULD be allocated if the <Sender Address, LSP-ID> fields
FILTER_SPEC object are the same. of the FILTER_SPEC object are the same.
However different upstream labels are allocated if the <Sender However different upstream labels are allocated if the <Sender
Address, LSP-ID> of the FILTER_SPEC object is different as that Address, LSP-ID> of the FILTER_SPEC object is different as that
implies different P2MP LSP. implies different P2MP LSP.
6.2. Resv Message Processing 6.2. Resv Message Processing
The egress LSR MUST follow normal RSVP procedures while originating a The egress LSR MUST follow normal RSVP procedures while originating a
Resv message. The Resv message carries the label allocated by the Resv message. The Resv message carries the label allocated by the
egress LSR. egress LSR.
A subsequent node MUST allocates its own label and pass it in the A node upstream of the egress node MUST allocate its own label and
Resv message upstream. The node MAY combine multiple flow descrip- pass it in the Resv message upstream. The node MAY combine multiple
tors, from different Resv messages received from downstream, in one flow descriptors, from different Resv messages received from
Resv message sent upstream. A Resv message MUST NOT be sent upstream downstream, in one Resv message sent upstream. A Resv message MUST
until at least one Resv message has been received from a downstream NOT be sent upstream until at least one Resv message has been
neighbor. When the integrity bit is set in the LSP_ATTRIBUTE object, received from a downstream neighbor. When the integrity bit is set in
no Resv message MUST be sent upstream until all Resv messages have the LSP_REQUIRED_ATTRIBUTE object, no Resv message MUST be sent
been received from the downstream neighbors. upstream until all Resv messages have been received from the
downstream neighbors.
Each FF flow descriptor or SE filter spec sent upstream in a Resv Each FF flow descriptor or SE filter spec sent upstream in a Resv
message includes a S2L sub-LSP descriptor list. Each such FF flow message includes a S2L sub-LSP descriptor list. Each such FF flow
descriptor or SE filter spec for the same P2MP LSP (whether on one or descriptor or SE filter spec for the same P2MP LSP (whether on one or
multiple Resv messages) MUST be allocated the same label. multiple Resv messages) on the same Resv MUST be allocated the same
label, and FF flow descriptors or SE filter specs SHOULD use the same
label across multiple Resv messages.
This label is associated by that node with all the labels received This label is associated by that node with all the labels received
from downstream Resv messages for that P2MP LSP. Note that a transit from downstream Resv messages for that P2MP LSP. Note that a transit
node may become a replication point in the future when a branch is node may become a replication point in the future when a branch is
attached to it. Hence this results in the setup of a P2MP LSP from attached to it. Hence this results in the setup of a P2MP LSP from
the ingress-LSR to the egress LSRs. the ingress-LSR to the egress LSRs.
The ingress LSR may need to understand when all desired egresses have The ingress LSR may need to understand when all desired egresses have
been reached. This is achieved using <S2L_SUB_LSP> objects. been reached. This is achieved using <S2L_SUB_LSP> objects.
Each branch node can potentially send one Resv message upstream for Each branch node can potentially send one Resv message upstream for
each of the downstream receivers. This MAY result in overflowing the each of the downstream receivers. This MAY result in overflowing the
Resv message, particularly when considering that the number of Resv message, particularly when considering that the number of
messages increases the closer the branch node is to the ingress of messages increases the closer the branch node is to the ingress of
the P2MP LSP. the P2MP LSP.
Transit nodes MUST replace the Sub-Group ID fields received in the Transit nodes MUST replace the Sub-Group ID fields received in the
FILTER_SPEC objects with the value that was received in the Sub-Group FILTER_SPEC objects with the value that was received in the Sub-Group
ID field of the Path message from the upstream neighbor, when the ID field of the Path message from the upstream neighbor, when the
node set the Sub-Group Originator field in the associated Path mes- node set the Sub-Group Originator field in the associated Path
sage. ResvErr messages generation is unmodified. Nodes propagating message. ResvErr messages generation is unmodified. Nodes
a received ResvErr message MUST use the Sub-Group field values propagating a received ResvErr message MUST use the Sub-Group field
carried in the corresponding Resv message. values carried in the corresponding Resv message.
6.2.1. Resv Message Throttling 6.2.1. Resv Message Throttling
A branch node may have to send the Resv message being sent upstream A branch node may have to send the Resv message being sent upstream
whenever there is a change in a Resv message for a S2L sub-LSP whenever there is a change in a Resv message for a S2L sub-LSP
received from one of the downstream neighbors. This can result in received from one of the downstream neighbors. This can result in
excessive Resv messages sent upstream,particularly when the S2L excessive Resv messages sent upstream,particularly when the S2L sub-
sub-LSPs are established for the first time. In order to mitigate LSPs are established for the first time. In order to mitigate this
this situation, branch nodes can limit their transmission of Resv mes- situation, branch nodes can limit their transmission of Resv
sages. Specifically, in the case where the only change being sent in messages. Specifically, in the case where the only change being sent
a Resv message is in one or more SRRO objects, the branch node SHOULD in a Resv message is in one or more SRRO objects, the branch node
transmit the Resv message only after a delay time has passed since SHOULD transmit the Resv message only after a delay time has passed
the transmission of the previous Resv message for the same session. since the transmission of the previous Resv message for the same
This delayed Resv message SHOULD include SRROs for all branches. session. This delayed Resv message SHOULD include SRROs for all
Specific mechanisms for Resv message throttling are implementation branches. Specific mechanisms for Resv message throttling are
dependent and are outside the scope of this document. implementation dependent and are outside the scope of this document.
6.3. Record Routing 6.3. Record Routing
6.3.1. RRO Processing 6.3.1. RRO Processing
A Resv message contains a record route per S2L sub-LSP that is being A Resv message contains a record route per S2L sub-LSP that is being
signaled by the Resv message if the sender node requests route signaled by the Resv message if the sender node requests route
recording by including a RRO in the Path message. The same rule is recording by including a RRO in the Path message. The same rule is
used during signaling of P2MP LSP i.e. insertion of the RRO in the used during signaling of P2MP LSP i.e. insertion of the RRO in the
Path message used to signal one or more S2L sub-LSP triggers the Path message used to signal one or more S2L sub-LSP triggers the
inclusion of an RRO for each sub-LSP. inclusion of an RRO for each sub-LSP.
The record route of the first S2L sub-LSP is encoded in the RRO. The record route of the first S2L sub-LSP is encoded in the RRO.
Additional RROs for the subsequent S2L sub-LSPs are referred to as Additional RROs for the subsequent S2L sub-LSPs are referred to as
P2MP_SECONDARY_RECORD_ROUTE objects (SRROs). Their format is speci- P2MP_SECONDARY_RECORD_ROUTE objects (SRROs). Their format is
fied in section 20.5. The ingress node then receives the RRO and specified in section 20.5. The ingress node then receives the RRO and
possibly the SRRO corresponding to each subsequent S2L sub-LSP. Each possibly the SRRO corresponding to each subsequent S2L sub-LSP. Each
<S2L_SUB_LSP> object is followed by the RRO/SRRO. The ingress node <S2L_SUB_LSP> object is followed by the RRO/SRRO. The ingress node
can then determine the record route corresponding to a particular S2L can then determine the record route corresponding to a particular S2L
sub-LSP. The RRO and SRROs can be used to construct the end to end sub-LSP. The RRO and SRROs can be used to construct the end to end
Path for each S2L sub-LSP. Path for each S2L sub-LSP.
6.4. Reservation Style 6.4. Reservation Style
Considerations about the reservation style in a Resv message apply as Considerations about the reservation style in a Resv message apply as
described in [RFC3209]. The reservation style in the Resv messages described in [RFC3209]. The reservation style in the Resv messages
can either be FF or SE. All P2MP LSP that belong to the same P2MP can either be FF or SE. All P2MP LSPs that belong to the same P2MP
Tunnel MUST be signaled with the same reservation style. Irrespective Tunnel MUST be signaled with the same reservation style. Irrespective
of whether the reservation style is FF or SE, the S2L sub-LSPs that of whether the reservation style is FF or SE, the S2L sub-LSPs that
belong to the same P2MP LSP SHOULD share labels where they share belong to the same P2MP LSP SHOULD share labels where they share
hops. If the S2L sub-LSPs that belong to the same P2MP LSP share hops. If the S2L sub-LSPs that belong to the same P2MP LSP share
labels then they MUST share resources. The S2L sub-LSPs that belong labels then they MUST share resources. The S2L sub-LSPs that belong
to different P2MP LSP MUST NOT share labels. If the reservation style to different P2MP LSP MUST NOT share labels. If the reservation style
is FF than S2L sub-LSPs that belong to different P2MP LSP MUST NOT is FF then S2L sub-LSPs that belong to different P2MP LSP MUST NOT
share resources. If the reservation style is SE than S2L sub-LSPs share resources. If the reservation style is SE than S2L sub-LSPs
that belong to different P2MP LSP and the same P2MP Tunnel SHOULD that belong to different P2MP LSP and the same P2MP Tunnel SHOULD
share resources where they share hops, but MUST not share labels. share resources where they share hops, but MUST not share labels.
7. PathTear Message 7. PathTear Message
7.1. PathTear Message Format 7.1. PathTear Message Format
The format of the PathTear message is as follows: The format of the PathTear message is as follows:
<PathTear Message> ::= <Common Header> [ <INTEGRITY> ] <PathTear Message> ::= <Common Header> [ <INTEGRITY> ]
[ [ <MESSAGE_ID_ACK> | [ [ <MESSAGE_ID_ACK> |
<MESSAGE_ID_NACK> ... ] <MESSAGE_ID_NACK> ... ]
[ <MESSAGE_ID> ] [ <MESSAGE_ID> ]
<SESSION> <RSVP_HOP> <SESSION> <RSVP_HOP>
[ <sender descriptor> ] [ <sender descriptor> ]
[ <S2L sub-LSP list> ] [ <S2L sub-LSP list> ]
<S2L sub-LSP list> ::= <S2L_SUB_LSP> [ <S2L sub-LSP list> ] <S2L sub-LSP list> ::= <S2L_SUB_LSP> [ <S2L sub-LSP list> ]
The definition of <sender descriptor> is not changed by this docu- The definition of <sender descriptor> is not changed by this
ment. document.
Note: it is assumed that the S2L sub-LSP descriptor will not include
the P2MP SECONDARY_EXPLICIT_ROUTE object associated with each S2L
sub-LSP being deleted.
7.2. Pruning 7.2. Pruning
The operation of removing egress LSR(s) from an existing P2MP LSP is The operation of removing egress LSR(s) from an existing P2MP LSP is
termed as pruning. This operation allows egress nodes to be removed termed as pruning. This operation allows egress nodes to be removed
from a P2MP LSP at different points in time. This section describes from a P2MP LSP at different points in time. This section describes
the mechanisms to perform pruning. the mechanisms to perform pruning.
7.2.1. Implicit S2L Sub-LSP Teardown 7.2.1. Implicit S2L Sub-LSP Teardown
Implicit teardown uses standard RSVP message processing. Per standard Implicit teardown uses standard RSVP message processing. Per standard
RSVP processing, a S2L sub-LSP may be removed from a P2MP TE LSP by RSVP processing, a S2L sub-LSP may be removed from a P2MP TE LSP by
sending a modified message for the Path or Resv message that previ- sending a modified message for the Path or Resv message that
ously advertised the S2L sub-LSP. This message MUST list all S2L previously advertised the S2L sub-LSP. This message MUST list all S2L
sub-LSPs that are not being removed. When using this approach, a node sub-LSPs that are not being removed. When using this approach, a node
processing a message that removes a S2L sub-LSP from a P2MP TE LSP processing a message that removes a S2L sub-LSP from a P2MP TE LSP
MUST ensure that the S2L sub-LSP is not included in any other Path MUST ensure that the S2L sub-LSP is not included in any other Path
state associated with session before interrupting the data path to state associated with session before interrupting the data path to
that egress. All other message processing remains unchanged. that egress. All other message processing remains unchanged.
When implicit teardown is used to delete one or more S2L sub-LSPs, by When implicit teardown is used to delete one or more S2L sub-LSPs, by
modifying a Path message, a transit LSR may have to generate a modifying a Path message, a transit LSR may have to generate a
PathTear message downstream to delete one or more of these S2L sub- PathTear message downstream to delete one or more of these S2L sub-
LSPs. This can happen if as a result of the implicit deletion of S2L LSPs. This can happen if as a result of the implicit deletion of S2L
sub-LSP(s) there are no remaining S2L sub-LSPs to send in the corre- sub-LSP(s) there are no remaining S2L sub-LSPs to send in the
sponding Path message downstream. corresponding Path message downstream.
7.2.2. Explicit S2L Sub-LSP Teardown 7.2.2. Explicit S2L Sub-LSP Teardown
Explicit S2L Sub-LSP teardown relies on generating a PathTear message Explicit S2L Sub-LSP teardown relies on generating a PathTear message
for the corresponding Path message. The PathTear message is signaled for the corresponding Path message. The PathTear message is signaled
with the SESSION and SENDER_TEMPLATE objects corresponding to the with the SESSION and SENDER_TEMPLATE objects corresponding to the
P2MP LSP and the <Sub-Group Originator ID, Sub-Group ID> tuple corre- P2MP LSP and the <Sub-Group Originator ID, Sub-Group ID> tuple
sponding to the Path message. This approach SHOULD be used when all corresponding to the Path message. This approach SHOULD be used when
the egresses signaled by a Path message need to be removed from the all the egresses signaled by a Path message need to be removed from
P2MP LSP. Other S2L sub-LSPs, from other sub-groups signaled using the P2MP LSP. Other S2L sub-LSPs, from other sub-groups signaled
other Path messages, are not affected by the PathTear. using other Path messages, are not affected by the PathTear.
A transit LSR that propagates the PathTear message downstream MUST A transit LSR that propagates the PathTear message downstream MUST
ensure that it sets the <Sub-Group Originator ID, Sub-Group ID> tuple ensure that it sets the <Sub-Group Originator ID, Sub-Group ID> tuple
in the PathTear message to the values used to generate the previous in the PathTear message to the values used to generate the previous
Path message that corresponds to the S2L sub-LSPs being deleted by it Path message that corresponds to the S2L sub-LSPs being deleted by it
in the PathTear message. The transit LSR may need to generate multi- in the PathTear message. The transit LSR may need to generate
ple PathTear messages for an incoming PathTear message if it had per- multiple PathTear messages for an incoming PathTear message if it had
formed transit fragmentation for the corresponding incoming Path mes- performed transit fragmentation for the corresponding incoming Path
sage. message.
When a P2MP LSP is removed by the ingress, a PathTear message MUST be When a P2MP LSP is removed by the ingress, a PathTear message MUST be
generated for each Path message used to signal the P2MP LSP. generated for each Path message used to signal the P2MP LSP.
8. Notify and ResvConf Messages 8. Notify and ResvConf Messages
8.1. Notify Messages 8.1. Notify Messages
The Notify Request object and Notify messages are described in The Notify Request object and Notify messages are described in
[RFC3473]. Both object and messages SHALL be supported for delivery [RFC3473]. Both object and messages SHALL be supported for delivery
skipping to change at page 21, line 25 skipping to change at page 22, line 5
this section MUST comply to [RFC3473]. this section MUST comply to [RFC3473].
1. Upstream Notification 1. Upstream Notification
If a transit LSR sets the Sub-Group Originator ID in the If a transit LSR sets the Sub-Group Originator ID in the
SENDER_TEMPLATE object of a Path message to its own address and the SENDER_TEMPLATE object of a Path message to its own address and the
incoming Path message carries a Notify Request object then this LSR incoming Path message carries a Notify Request object then this LSR
MUST change the Notify node address in the Notify Request object to MUST change the Notify node address in the Notify Request object to
its own address in the Path message that it sends. its own address in the Path message that it sends.
If this router subsequently receives a corresponding Notify message If this LSR subsequently receives a corresponding Notify message from
from a downstream LSR than it MUST: a downstream LSR than it MUST:
- send a Notify message upstream toward the Notify - send a Notify message upstream toward the Notify
node address that the LSR received in the Path message. node address that the LSR received in the Path message.
- process the sub-group fields of the SENDER_TEMPLATE - process the sub-group fields of the SENDER_TEMPLATE
object on the received Notify message, and modify their values object on the received Notify message, and modify their values
in the Notify message that is forwarded to match the sub-group in the Notify message that is forwarded to match the sub-group
field values in the original Path message received from upstream. field values in the original Path message received from upstream.
The receiver of an (upstream) Notify message MUST identify the state The receiver of an (upstream) Notify message MUST identify the state
referenced in this message based on the SESSION and SENDER_TEMPLATE. referenced in this message based on the SESSION and SENDER_TEMPLATE.
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2. Downstream Notification 2. Downstream Notification
A transit LSR sets the Sub-Group Originator ID in the FILTER_SPEC A transit LSR sets the Sub-Group Originator ID in the FILTER_SPEC
object(s) of a Resv message to the value, that was received in the object(s) of a Resv message to the value, that was received in the
corresponding Path message. If the incoming Resv message carries a corresponding Path message. If the incoming Resv message carries a
Notify Request object then the LSR MUST set the Notify node address Notify Request object then the LSR MUST set the Notify node address
in the Notify Request object to the value, that was received in the in the Notify Request object to the value, that was received in the
corresponding Path message, in the Resv message that it sends corresponding Path message, in the Resv message that it sends
upstream. upstream.
If this router subsequently receives a corresponding Notify message If this LSR subsequently receives a corresponding Notify message from
from upstream LSR than it MUST: an upstream LSR than it MUST:
- send a Notify message downstream toward the Notify - send a Notify message downstream toward the Notify
node address that the LSR received in the Resv message. node address that the LSR received in the Resv message.
- process the sub-group fields of the FILTER_SPEC object in the - process the sub-group fields of the FILTER_SPEC object in the
received Notify message, and modify their values in the Notify received Notify message, and modify their values in the Notify
message that is forwarded to match the sub-group field values message that is forwarded to match the sub-group field values
in the original Path message sent downstream by this LSR. in the original Path message sent downstream by this LSR.
The receiver of a (downstream) Notify message MUST identify the state The receiver of a (downstream) Notify message MUST identify the state
referenced in this message based on the SESSION and FILTER_SPEC referenced in the message based on the SESSION and FILTER_SPEC
objects. objects.
The consequence of these rules for a P2MP LSP is that an upstream The consequence of these rules for a P2MP LSP is that an upstream
Notify message generated on a branch will result in a Notify being Notify message generated on a branch will result in a Notify being
delivered to the upstream Notify node address. The receiver of the delivered to the upstream Notify node address. The receiver of the
Notify message MUST NOT assume that the Notify message applies to all Notify message MUST NOT assume that the Notify message applies to all
downstream egresses, but MUST examine the information in the message downstream egresses, but MUST examine the information in the message
to determine to which egresses the message applies. to determine to which egresses the message applies.
Downstream Notify messages MUST be replicated at branch LSRs accord- Downstream Notify messages MUST be replicated at branch LSRs
ing to the Notify Request objects received on Resv messages. Some according to the Notify Request objects received on Resv messages.
downstream branches might not request Notify messages, but all that Some downstream branches might not request Notify messages, but all
have requested Notify messages MUST receive them that have requested Notify messages MUST receive them
8.2. ResvConf Messages 8.2. ResvConf Messages
ResvConf messages are described in [RFC2205]. ResvConf processing in ResvConf messages are described in [RFC2205]. ResvConf processing in
[RFC3473] and [RFC3209] is taken directly from [RFC2205]. An egress [RFC3473] and [RFC3209] is taken directly from [RFC2205]. An egress
LSR may include a RESV_CONFIRM object that contains the egress LSR's LSR may include a RESV_CONFIRM object that contains the egress LSR's
address. The object and message SHALL be supported for the confirma- address. The object and message SHALL be supported for the
tion of receipt of the Resv message in P2MP TE LSPs. Processing not confirmation of receipt of the Resv message in P2MP TE LSPs.
detailed in this section MUST comply to [RFC2205]. Processing not detailed in this section MUST comply to [RFC2205].
A transit LSR sets the Sub-Group Originator ID in the FILTER_SPEC A transit LSR sets the Sub-Group Originator ID in the FILTER_SPEC
object(s) of a Resv message to the value, that was received in the object(s) of a Resv message to the value, that was received in the
corresponding Path message. If the incoming Resv message carries a corresponding Path message. If any of the incoming Resv messages
RESV_CONFIRM object then the LSR MUST include a RESV_CONFIRM object corresponding to a single Path message carry a RESV_CONFIRM object
in the corresponding Resv message that it sends upstream and MUST set then the LSR MUST include a RESV_CONFIRM object in the corresponding
the receiver address in the RESV_CONFIRM object to the value that was Resv message that it sends upstream and MUST set the receiver address
received in the corresponding Path message. in the RESV_CONFIRM object to the value that was received in the
corresponding Resv message.
If this router subsequently receives a corresponding ResvConf message If this LSR subsequently receives a corresponding ResvConf message
from an upstream LSR than it MUST: from an upstream LSR than it MUST:
- send a ResvConf message downstream toward the receiver address that - send a ResvConf message downstream toward the receiver address that
the LSR received in the RESV_CONFIRM object in the Resv message. the LSR received in the RESV_CONFIRM object in the Resv message.
- process the sub-group fields of the FILTER_SPEC object in the - process the sub-group fields of the FILTER_SPEC object in the
received ResvConf message, and modify their values in the ResvConf received ResvConf message, and modify their values in the ResvConf
message that is forwarded to match the sub-group field values message that is forwarded to match the sub-group field values
in the original Path message sent downstream by this LSR. in the original Path message sent downstream by this LSR.
The receiver of a ResvConf message MUST identify the state referenced The receiver of a ResvConf message MUST identify the state referenced
in this message based on the SESSION and FILTER_SPEC objects. in this message based on the SESSION and FILTER_SPEC objects.
The consequence of these rules for a P2MP LSP is that a ResvConf mes- The consequence of these rules for a P2MP LSP is that a ResvConf
sage generated at the ingress will result in a ResvConf message being message generated at the ingress will result in a ResvConf message
delivered to the branch and then to the receiver address in the orig- being delivered to the branch and then to the receiver address in the
inal RESV_CONFIRM object. The receiver of a ResvConf message MUST NOT original RESV_CONFIRM object. The receiver of a ResvConf message MUST
assume that the ResvConf message should be sent to all downstream NOT assume that the ResvConf message should be sent to all downstream
egresses, but MUST replicate the message according to the egresses, but MUST replicate the message according to the
RESV_CONFIRM objects received in Resv messages. Some downstream branches RESV_CONFIRM objects received in Resv messages. Some downstream
branches might not request ResvConf messages, and ResvConf messages branches might not request ResvConf messages, and ResvConf messages
SHOULD NOT be on these branches. All downstream branches that do SHOULD NOT be sent on these branches. All downstream branches that do
requested ResvConf messages MUST be sent such a message. requested ResvConf messages MUST be sent such a message.
9. Refresh Reduction 9. Refresh Reduction
The refresh reduction procedures described in [RFC2961] are equally The refresh reduction procedures described in [RFC2961] are equally
applicable to P2MP LSP described in this document. Refresh reduction applicable to P2MP LSP described in this document. Refresh reduction
applies to individual messages and the state they install/maintain, applies to individual messages and the state they install/maintain,
and that continues to be the case for P2MP LSP. and that continues to be the case for P2MP LSP.
10. State Management 10. State Management
State signaled by a P2MP Path message is managed by a local implemen- State signaled by a P2MP Path message is managed by a local
tation using the <P2MP ID, Tunnel ID, Extended Tunnel ID> as part of implementation using the <P2MP ID, Tunnel ID, Extended Tunnel ID> as
the SESSION object and <Tunnel Sender Address, LSP ID, Sub-Group part of the SESSION object and <Tunnel Sender Address, LSP ID, Sub-
Originator ID, Sub-Group ID> as part of the SENDER_TEMPLATE object. Group Originator ID, Sub-Group ID> as part of the SENDER_TEMPLATE
object.
Additional information signaled in the Path/Resv message is part of Additional information signaled in the Path/Resv message is part of
the state created by a local implementation. This mandatorily the state created by a local implementation. This includes PHOP/NHOP
includes PHOP/NHOP and SENDER_TSPEC/FILTER_SPEC object. and SENDER_TSPEC/FILTER_SPEC object.
10.1. Incremental State Update 10.1. Incremental State Update
RSVP as defined in [RFC2205] and as extended by RSVP-TE [RFC3209] and RSVP as defined in [RFC2205] and as extended by RSVP-TE [RFC3209] and
GMPLS [RFC3473] uses the same basic approach to state communication GMPLS [RFC3473] uses the same basic approach to state communication
and synchronization, namely full state is sent in each state adver- and synchronization, namely full state is sent in each state
tisement message. Per [RFC2205] Path and Resv messages are idempo- advertisement message. Per [RFC2205] Path and Resv messages are
tent. Also, [RFC2961] categorizes RSVP messages into two types: trig- idempotent. Also, [RFC2961] categorizes RSVP messages into two types:
ger and refresh messages and improves RSVP message handling and scal- trigger and refresh messages and improves RSVP message handling and
ing of state refreshes but does not modify the full state advertise- scaling of state refreshes but does not modify the full state
ment nature of Path and Resv messages. The full state advertisement advertisement nature of Path and Resv messages. The full state
nature of Path and Resv messages has many benefits, but also has some advertisement nature of Path and Resv messages has many benefits, but
drawbacks. One notable drawback is when an incremental modification also has some drawbacks. One notable drawback is when an incremental
is being made to a previously advertised state. In this case, there modification is being made to a previously advertised state. In this
is the message overhead of sending the full state and the cost of case, there is the message overhead of sending the full state and the
processing it. It is desirable to overcome this drawback and cost of processing it. It is desirable to overcome this drawback and
add/delete S2L sub-LSPs to a P2MP LSP by incrementally updating the add/delete S2L sub-LSPs to a P2MP LSP by incrementally updating the
existing state. existing state.
It is possible to use the procedures described in this document to It is possible to use the procedures described in this document to
allow S2L sub-LSPs to be incrementally added or deleted from the P2MP allow S2L sub-LSPs to be incrementally added or deleted from the P2MP
LSP by allowing a Path or a PathTear message to incrementally change LSP by allowing a Path or a PathTear message to incrementally change
the existing P2MP LSP Path state. the existing P2MP LSP Path state.
As described in section 4.2, multiple Path messages can be used to As described in section 4.2, multiple Path messages can be used to
signal a P2MP LSP. The Path messages are distinguished by different signal a P2MP LSP. The Path messages are distinguished by different
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This maintains the idempotent nature of RSVP Path messages; avoids This maintains the idempotent nature of RSVP Path messages; avoids
keeping track of individual S2L sub-LSP state expiration and provides keeping track of individual S2L sub-LSP state expiration and provides
the ability to perform incremental P2MP LSP state updates. the ability to perform incremental P2MP LSP state updates.
10.2. Combining Multiple Path Messages 10.2. Combining Multiple Path Messages
There is a tradeoff between the number of Path messages used by the There is a tradeoff between the number of Path messages used by the
ingress to maintain the P2MP LSP and the processing imposed by full ingress to maintain the P2MP LSP and the processing imposed by full
state messages when adding S2L sub-LSPs to an existing Path message. state messages when adding S2L sub-LSPs to an existing Path message.
It is possible to combine S2L sub-LSPs previously advertised in dif- It is possible to combine S2L sub-LSPs previously advertised in
ferent Path messages in a single Path message in order to reduce the different Path messages in a single Path message in order to reduce
number of Path messages needed to maintain the P2MP LSP. This can the number of Path messages needed to maintain the P2MP LSP. This can
also be done by a transit node that performed fragmentation and at a also be done by a transit node that performed fragmentation and at a
later point is able to combine multiple Path messages that it gener- later point is able to combine multiple Path messages that it
ated into a single Path message. This may happen when one or more S2L generated into a single Path message. This may happen when one or
sub-LSPs are pruned from the existing Path states. more S2L sub-LSPs are pruned from the existing Path states.
The new Path message is signaled by the node that is combining multi- The new Path message is signaled by the node that is combining
ple Path messages with all the S2L sub-LSPs that are being combined multiple Path messages with all the S2L sub-LSPs that are being
in a single Path message. This Path message MAY contain a new Sub- combined in a single Path message. This Path message MAY contain a
Sub-Group ID field value. When a new Path and Resv message that is new Sub-Group ID field value. When a new Path and Resv message that
signaled for an existing S2L sub-LSP is received by a transit LSR, is signaled for an existing S2L sub-LSP is received by a transit LSR,
state including the new instance of the S2L sub-LSP is created. state including the new instance of the S2L sub-LSP is created.
The S2L sub-LSP SHOULD continue to be advertised in both the old and The S2L sub-LSP SHOULD continue to be advertised in both the old and
new Path messages until a Resv message listing the S2L sub-LSP and new Path messages until a Resv message listing the S2L sub-LSP and
corresponding to the new Path message is received by the combining corresponding to the new Path message is received by the combining
node. Hence until this point state for the S2L sub-LSP SHOULD be node. Hence until this point state for the S2L sub-LSP SHOULD be
maintained as part of the Path state for both the old and the new maintained as part of the Path state for both the old and the new
Path message [Section 3.1.3, RFC2205]. At that point the S2L sub-LSP Path message [Section 3.1.3, RFC2205]. At that point the S2L sub-LSP
SHOULD be deleted from the old Path state using the procedures of SHOULD be deleted from the old Path state using the procedures of
section 7. section 7.
A Path message with a sub-Group_ID(n) may signal a set of S2L A Path message with a sub-Group_ID(n) may signal a set of S2L sub-
sub-LSPs that belong partially or entirely to an already existing LSPs that belong partially or entirely to an already existing Sub-
Sub-Group_ID(i), the SESSION object and <Sender Tunnel Address, Group_ID(i), the SESSION object and <Sender Tunnel Address, LSP-ID,
LSP-ID, Sub-Group Originator ID> being the same. Or it may signal a Sub-Group Originator ID> being the same. Or it may signal a strictly
strictly non-overlapping new set of S2L sub-LSPs with a strictly higher non-overlapping new set of S2L sub-LSPs with a strictly higher sub-
sub-Group_ID value. Group_ID value.
1) If sub-Group_ID(i) = sub-Group_ID(n), then either a full refresh 1) If sub-Group_ID(i) = sub-Group_ID(n), then either a full refresh
is indicated by the Path message or a S2L Sub-LSP is added to/deleted is indicated by the Path message or a S2L Sub-LSP is added to/deleted
from the group signaled by sub-Group_ID(n) from the group signaled by sub-Group_ID(n)
2) If sub-Group_ID(i) != sub-Group_ID(n), then the Path message is 2) If sub-Group_ID(i) != sub-Group_ID(n), then the Path message is
signaling a set of S2L sub-LSPs that belong partially or entirely to signaling a set of S2L sub-LSPs that belong partially or entirely to
an already existing Sub-Group_ID(i) or a strictly non-overlapping set an already existing Sub-Group_ID(i) or a strictly non-overlapping set
of S2L sub-LSPs. of S2L sub-LSPs.
11. Error Processing 11. Error Processing
PathErr and ResvErr messages are processed as per RSVP-TE procedures. PathErr and ResvErr messages are processed as per RSVP-TE procedures.
Note that a LSR on receiving a PathErr/ResvErr message for a particu- Note that an LSR on receiving a PathErr/ResvErr message for a
lar S2L sub-LSP changes the state only for that S2L sub-LSP. Hence particular S2L sub-LSP changes the state only for that S2L sub-LSP.
other S2L sub-LSPs are not impacted. In case the ingress node Hence other S2L sub-LSPs are not impacted. If the ingress node
requests the maintenance of the 'LSP integrity', any error reported requests the maintenance of the 'LSP integrity', any error reported
within the P2MP TE LSP must be reported at (least at) any other within the P2MP TE LSP must be reported to (at least) any other
branching nodes belonging to this LSP. Therefore, reception of an branching nodes belonging to this LSP. Therefore, reception of an
error message for a particular S2L sub-LSP MAY change the state of error message for a particular S2L sub-LSP MAY change the state of
any other S2L sub- LSP of the same P2MP TE LSP. any other S2L sub- LSP of the same P2MP TE LSP.
11.1. PathErr Messages 11.1. PathErr Messages
The PathErr message will include one or more <S2L_SUB_LSP> objects. The PathErr message will include one or more <S2L_SUB_LSP> objects.
The resulting modified format for a PathErr message is: The resulting modified format for a PathErr message is:
<PathErr Message> ::= <Common Header> [ <INTEGRITY> ] <PathErr Message> ::= <Common Header> [ <INTEGRITY> ]
skipping to change at page 26, line 11 skipping to change at page 26, line 43
[ <ACCEPTABLE_LABEL_SET> ... ] [ <ACCEPTABLE_LABEL_SET> ... ]
[ <POLICY_DATA> ... ] [ <POLICY_DATA> ... ]
<sender descriptor> <sender descriptor>
[ <S2L sub-LSP descriptor list> ] [ <S2L sub-LSP descriptor list> ]
PathErr messages generation is unmodified, but nodes that set the PathErr messages generation is unmodified, but nodes that set the
Sub-Group Originator field and propagate a received PathErr message Sub-Group Originator field and propagate a received PathErr message
upstream MUST replace the Sub-Group fields received in the PathErr upstream MUST replace the Sub-Group fields received in the PathErr
message with the value that was received in the Sub-Group fields of message with the value that was received in the Sub-Group fields of
the Path message from the upstream neighbor. Note the receiver of a the Path message from the upstream neighbor. Note the receiver of a
PathErr message is able to identify the errored outgoing Path mes- PathErr message is able to identify the errored outgoing Path
sage, and outgoing interface, based on the Sub-Group fields received message, and outgoing interface, based on the Sub-Group fields
in the PathErr message. received in the PathErr message.
11.2. ResvErr Messages 11.2. ResvErr Messages
The ResvErr message will include one or more <S2L_SUB_LSP> objects. The ResvErr message will include one or more <S2L_SUB_LSP> objects.
The resulting modified format for a ResvErr Message is: The resulting modified format for a ResvErr Message is:
<ResvErr Message> ::= <Common Header> [ <INTEGRITY> ] <ResvErr Message> ::= <Common Header> [ <INTEGRITY> ]
[ [<MESSAGE_ID_ACK> | [ [<MESSAGE_ID_ACK> |
<MESSAGE_ID_NACK>] ... ] <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ] [ <MESSAGE_ID> ]
skipping to change at page 26, line 35 skipping to change at page 27, line 25
<ERROR_SPEC> [ <SCOPE> ] <ERROR_SPEC> [ <SCOPE> ]
[ <ACCEPTABLE_LABEL_SET> ... ] [ <ACCEPTABLE_LABEL_SET> ... ]
[ <POLICY_DATA> ... ] [ <POLICY_DATA> ... ]
<STYLE> <flow descriptor list> <STYLE> <flow descriptor list>
ResvErr messages generation is unmodified, but nodes that set the ResvErr messages generation is unmodified, but nodes that set the
Sub-Group Originator field and propagate a received ResvErr message Sub-Group Originator field and propagate a received ResvErr message
downstream MUST replace the Sub-Group fields received in the ResvErr downstream MUST replace the Sub-Group fields received in the ResvErr
message with the value that was set in the Sub-Group fields of the message with the value that was set in the Sub-Group fields of the
Path message sent to the downstream neighbor. Note the receiver of a Path message sent to the downstream neighbor. Note the receiver of a
ResvErr message is able to identify the errored outgoing Path mes- ResvErr message is able to identify the errored outgoing Path
sage, and outgoing interface, based on the Sub-Group fields received message, and outgoing interface, based on the Sub-Group fields
in the ResvErr message. received in the ResvErr message.
11.3. Branch Failure Handling 11.3. Branch Failure Handling
During setup and during normal operation, PathErr messages may be During setup and during normal operation, PathErr messages may be
received at a branch node. In all cases, a received PathErr message received at a branch node. In all cases, a received PathErr message
is first processed per standard processing rules. That is: the is first processed per standard processing rules. That is: the
PathErr message is sent hop-by-hop to the ingress/branch LSR for that PathErr message is sent hop-by-hop to the ingress/branch LSR for that
Path message. Intermediate nodes until this ingress/branch LSR MAY Path message. Intermediate nodes until this ingress/branch LSR MAY
inspect this message but take no action upon it. The behavior of a inspect this message but take no action upon it. The behavior of a
branch LSR that generates a PathErr message is under the control of branch LSR that generates a PathErr message is under the control of
the ingress LSR. the ingress LSR.
The default behavior is that the PathErr message does not have the The default behavior is that the PathErr message does not have the
Path_State_Removed flag set. However, if the ingress LSR has set the Path_State_Removed flag set. However, if the ingress LSR has set the
LSP integrity flag on the Path message (see LSP_ATTRIBUTE object in LSP integrity flag on the Path message (see LSP_REQUIRED_ATTRIBUTEs
section 20) and if the Path_State_Removed flag is supported, the LSR object in section 5.2.4) and if the Path_State_Removed flag is
generating a PathErr to report the failure of a branch of the P2MP supported, the LSR generating a PathErr to report the failure of a
LSP SHOULD set the Path_State_Removed flag. branch of the P2MP LSP SHOULD set the Path_State_Removed flag.
A branch LSR that receives a PathErr message with the A branch LSR that receives a PathErr message with the
Path_State_Removed flag set MUST act according to the wishes of the Path_State_Removed flag set MUST act according to the wishes of the
ingress LSR. The default behavior is that the branch LSR clears the ingress LSR. The default behavior is that the branch LSR clears the
Path_State_Removed flag on the PathErr and sends it further upstream. Path_State_Removed flag on the PathErr and sends it further upstream.
It does not tear any other branches of the LSP. However, if the LSP It does not tear any other branches of the LSP. However, if the LSP
integrity flag is set on the Path message, the branch LSR MUST send integrity flag is set on the Path message, the branch LSR MUST send
PathTear on all other downstream branches and send the PathErr mes- PathTear on all other downstream branches and send the PathErr
sage upstream with the Path_State_Removed flag set. message upstream with the Path_State_Removed flag set.
A branch LSR that receives a PathErr message with the A branch LSR that receives a PathErr message with the
Path_State_Removed flag clear MUST act according to the wishes of the Path_State_Removed flag clear MUST act according to the wishes of the
ingress LSR. The default behavior is that the branch LSR forwards the ingress LSR. The default behavior is that the branch LSR forwards the
PathErr upstream and takes no further action. However, if the LSP PathErr upstream and takes no further action. However, if the LSP
integrity flag is set on the Path message, the branch LSR MUST send integrity flag is set on the Path message, the branch LSR MUST send
PathTear on all downstream branches and send the PathErr upstream PathTear on all downstream branches and send the PathErr upstream
with the Path_State_Removed flag set (per [RFC3473]). with the Path_State_Removed flag set (per [RFC3473]).
In all cases, the PathErr message forwarded by a branch LSR MUST con- In all cases, the PathErr message forwarded by a branch LSR MUST
tain the S2L sub-LSP identification and explicit routes of all contain the S2L sub-LSP identification and explicit routes of all
branches that are reported by received PathErr messages and all branches that are reported by received PathErr messages and all
branches that are explicitly torn by the branch LSR. branches that are explicitly torn by the branch LSR.
12. Admin Status Change 12. Admin Status Change
A branch node that receives an ADMIN_STATUS object processes it nor- A branch node that receives an ADMIN_STATUS object processes it
mally and also relays the ADMIN_STATUS object in a Path on every normally and also relays the ADMIN_STATUS object in a Path on every
branch. All Path messages may be concurrently sent to the downstream branch. All Path messages may be concurrently sent to the downstream
neighbors. neighbors.
Downstream nodes process the change in the status object per Downstream nodes process the change in the ADMIN_STATUS object per
[RFC3473], including generation of Resv messages. When the last [RFC3473], including generation of Resv messages. When the last
received upstream ADMIN_STATUS object had the R bit set, branch nodes received upstream ADMIN_STATUS object had the R bit set, branch nodes
wait for a Resv message with a matching ADMIN_STATUS object to be wait for a Resv message with a matching ADMIN_STATUS object to be
received (or a corresponding PathErr or ResvTear messsage) on all received (or a corresponding PathErr or ResvTear messsage) on all
branches before relaying a corresponding Resv message upstream. branches before relaying a corresponding Resv message upstream.
13. Label Allocation on LANs with Multiple Downstream Nodes 13. Label Allocation on LANs with Multiple Downstream Nodes
A sender on a LAN uses a different label for sending traffic to each A sender on a LAN uses a different label for sending traffic to each
node on the LAN that belongs to the P2MP LSP. Thus the sender per- node on the LAN that belongs to the P2MP LSP. Thus the sender
forms replication. It may be considered desirable on a LAN to use the performs replication. It may be considered desirable on a LAN to use
same label for sending traffic to multiple nodes belonging to the the same label for sending traffic to multiple nodes belonging to the
same P2MP LSP, to avoid replication. Procedures for doing this are same P2MP LSP, to avoid replication. Procedures for doing this are
for further study. for further study.
14. P2MP LSP and Sub-LSP Re-optimization 14. P2MP LSP and Sub-LSP Re-optimization
It is possible to change the path used by P2MP LSPs to reach the des- It is possible to change the path used by P2MP LSPs to reach the
tinations of the P2MP Tunnel. There are two methods that can be used destinations of the P2MP Tunnel. There are two methods that can be
to accomplish this. The first is make-before-break, defined in used to accomplish this. The first is make-before-break, defined in
[RFC3209], and the second uses the sub-groups defined above. [RFC3209], and the second uses the sub-groups defined above.
14.1. Make-before-break 14.1. Make-before-break
In this case all the S2L sub-LSPs are signaled with a different LSP In this case all the S2L sub-LSPs are signaled with a different LSP
ID by the ingress-LSR and follow make-before-break procedure defined ID by the ingress-LSR and follow make-before-break procedure defined
in [RFC3209]. Thus a new P2MP LSP is established. Each S2L sub-LSP is in [RFC3209]. Thus a new P2MP LSP is established. Each S2L sub-LSP is
signaled with a different LSP ID, corresponding to the new P2MP LSP. signaled with a different LSP ID, corresponding to the new P2MP LSP.
After moving traffic to the new P2MP LSP, the ingress can tear down After moving traffic to the new P2MP LSP, the ingress can tear down
the old P2MP LSP. This procedure can be used to re-optimize the path the old P2MP LSP. This procedure can be used to re-optimize the path
skipping to change at page 28, line 40 skipping to change at page 29, line 31
the P2MP LSP. When modifying just a portion of the P2MP LSP this the P2MP LSP. When modifying just a portion of the P2MP LSP this
approach requires the entire P2MP LSP to be resignaled. approach requires the entire P2MP LSP to be resignaled.
14.2. Sub-Group Based Re-optimization 14.2. Sub-Group Based Re-optimization
Any node may initiate re-optimization of a set of S2L sub-LSPs by Any node may initiate re-optimization of a set of S2L sub-LSPs by
using the incremental state update and then, optionally, combining using the incremental state update and then, optionally, combining
multiple path messages. multiple path messages.
To alter the path taken by a particular set of S2L sub-LSPs the node To alter the path taken by a particular set of S2L sub-LSPs the node
initiating the path change initiates one or more separate Path mes- initiating the path change initiates one or more separate Path
sages, for the same P2MP LSP, each with a new sub-Group ID. The gen- messages, for the same P2MP LSP, each with a new sub-Group ID. The
eration of these Path messages, each with one or more S2L sub-LSPs, generation of these Path messages, each with one or more S2L sub-
follows procedures in section 5.2. As is the case in Section 10.2, a LSPs, follows procedures in section 5.2. As is the case in Section
particular egress continues to be advertised in both the old and new 10.2, a particular egress continues to be advertised in both the old
Path messages until a Resv message listing the egress and correspond- and new Path messages until a Resv message listing the egress and
ing to the new Path message is received by the re-optimizing node. At corresponding to the new Path message is received by the re-
that point the egress SHOULD be deleted from the old Path state using optimizing node. At that point the egress SHOULD be deleted from the
the procedures of section 7. Sub-tree re-optimization is then com- old Path state using the procedures of section 7. Sub-tree re-
pleted. optimization is then completed.
As is always the case, a node may choose to combine multiple path As is always the case, a node may choose to combine multiple path
messages as described in section 10.2. messages as described in section 10.2.
15. Fast Reroute 15. Fast Reroute
[RFC4090] extensions can be used to perform fast reroute for the [RFC4090] extensions can be used to perform fast reroute for the
mechanism described in this document. mechanism described in this document. This section uses terminology
defined in [RFC4090] and fast reroute procedures defined in [RFC4090]
MUST be followed unless specified below. The head-end and transit
LSRs MUST follow the SESSION_ATTRIBUTE and FAST_REROUTE object
processing as specified in [RFC4090] for each Path message and S2L
sub-LSP of a P2MP LSP. Each S2L sub-LSP of a P2MP LSP MUST have the
same protection characteristics. The RRO processing MUST apply to
SRRO as well unless modified below.
15.1. Facility Backup 15.1. Facility Backup
Facility backup as described in [RFC4090] can be used to protect P2MP Facility backup can be used for link or node protection of LSRs on
LSPs. the path of a P2MP LSP. The downstream labels MUST be learned by the
PLR as specified in [RFC4090] from the label corresponding to the S2L
sub-LSP in the RESV message. SERO processing for SEROs signaled in a
backup tunnel MUST follow backup tunnel ERO processing described in
[RFC4090].
If link protection is desired, a bypass tunnel is used to protect the 15.1.1. Link Protection
link between the PLR and next-hop. Thus all S2L sub-LSPs that use the
link can be protected in the event of link failure. Note that all
such S2L sub-LSPs belonging to a particular instance of a P2MP tunnel
will share the same outgoing label on the link between the PLR and
the next-hop. This is the P2MP LSP label on the link. Label stacking
is used to send data for each P2MP LSP in the bypass tunnel. The
inner label is the P2MP LSP label allocated by the nhop. During fail-
ure Path messages for each S2L sub-LSP, that is effected, will be
sent to the MP, by the PLR. It is recommended that the PLR use the
sender template specific method to identify these Path messages.
Hence the PLR will set the source address in the sender template to a
local PLR address. The MP will use the LSP-ID to identify the corre-
sponding S2L sub-LSPs.
The MP MUST not use the <sub-group originator ID, sub-group ID> while If link protection is desired, a bypass tunnel MUST be used to
identifying the corresponding S2L sub-LSPs. protect the link between the PLR and next-hop. Thus all S2L sub-LSPs
that use the link MUST be protected in the event of link failure.
Note that all such S2L sub-LSPs belonging to a particular instance of
a P2MP tunnel will share the same outgoing label on the link between
the PLR and the next-hop. This is the P2MP LSP label on the link.
Label stacking is used to send data for each P2MP LSP into the bypass
tunnel. The inner label is the P2MP LSP label allocated by the next-
hop. During failure Path messages for each S2L sub-LSP, that are
effected, MUST be sent to the MP, by the PLR. It is recommended that
the PLR use the sender template specific method to identify these
Path messages. Hence the PLR will set the source address in the
sender template to a local PLR address. The MP MUST use the LSP-ID to
identify the corresponding S2L sub-LSPs. The MP MUST not use the
<sub-group originator ID, sub-group ID> while identifying the
corresponding S2L sub-LSPs. In order to further process a S2L sub-LSP
the MP MUST determine the protected S2L sub-LSP using the LSP-id and
the <S2L_SUB_LSP> object.
In order to further process a S2L sub-LSP it will determine the pro- 15.1.2. Node Protection
tected S2L sub-LSP using the LSP-id and the <S2L_SUB_LSP> object.
If node protection is desired, the bypass P2P tunnel must intersect If node protection is desired the PLR MUST use one or more P2P bypass
the path of the protected S2L sub-LSPs on a LSR that is downstream tunnels to protect the set of S2L sub-LSPs that transit the protected
from the PLR. This constrains the set of S2L sub-LSPs being backed-up node. Each of these P2P bypass tunnels MUST intersect the path of the
via that bypass tunnel to those S2L sub-LSPs that pass through a com- S2L sub-LSPs that they protect on a LSR that is downstream from the
mon downstream MP. This MP is the destination of the bypass tunnel. protected node. This constrains the set of S2L sub-LSPs being backed
The MP will allocate the same label to all such S2L sub-LSPs belong- up via that bypass tunnel to those S2L sub-LSPs that pass through a
ing to a particular instance of a P2MP tunnel. This will be the inner common downstream MP. This MP is the destination of the bypass
label used during label stacking by the PLR when it sends data for tunnel. The MP MUST allocate the same label to all such S2L sub-LSPs
each P2MP LSP in the bypass tunnel. The outer label is the bypass belonging to a particular P2MP LSP. This is the inner label used
tunnel label. During failure of the protected node the PLR will send during label stacking by the PLR when it sends data for each P2MP LSP
Path messages for the protected S2L sub-LSPs to the MP using into the bypass tunnel. The outer label is the bypass tunnel label.
procedures that are same as the link protection procedures described
above. Node protection may require the PLR to be branch capable as After detecting failure of the protected node the PLR MUST send a
multiple bypass tunnels may be required to backup the set of S2L sub- Path message for each protected S2L sub-LSP to the MP of the
LSPs passing through the protected node. Else all the S2L sub-LSPs protected S2L sub-LSP. It is recommended that the PLR use the sender
passing through the protected node must also pass through a MP that template specific method to identify these Path messages. Hence the
is downstream from the protected node. PLR will set the source address in the sender template to a local PLR
address. The MP MUST use the LSP-ID to identify the corresponding S2L
sub-LSPs. The MP MUST not use the <sub-group originator ID, sub-group
ID> while identifying the corresponding S2L sub-LSPs. In order to
further process a S2L sub-LSP the MP MUST determine the protected S2L
sub-LSP using the LSP-id and the <S2L_SUB_LSP> object.
Note that node protection MAY require the PLR to be branch capable in
the data plane as multiple bypass tunnels may be required to backup
the set of S2L sub-LSPs passing through the protected node. If the
PLR is not branch capable, the node protection mechanism described
here is applicable to only those cases where all the S2L sub-LSPs
passing through the protected node also pass through a single MP that
is downstream from the protected node. Procedures for node protection
when a PLR is not branch capable and all the protected S2L sub-LSPs
do not pass through a single MP that is downstream from the protected
node are for further study. It is also to be noted that procedures in
this section require P2P bypass tunnels. Procedures for using P2MP
bypass tunnels are for further study.
15.2. One to One Backup 15.2. One to One Backup
One to one backup as described in [RFC4090] can be used to protect a One to one backup as described in [RFC4090] can be used to protect a
particular S2L sub-LSP against link and next-hop failure. Protection particular S2L sub-LSP against link and next-hop failure. Protection
may be used for one or more S2L sub-LSPs between the PLR and the may be used for one or more S2L sub-LSPs between the PLR and the
next-hop. All the S2L sub-LSPs corresponding to the same instance of next-hop. All the S2L sub-LSPs corresponding to the same instance of
the P2MP tunnel, between the PLR and the next-hop share the same P2MP the P2MP tunnel, between the PLR and the next-hop share the same P2MP
LSP label. LSP label.
All or some of these S2L sub-LSPs may be protected. All or some of these S2L sub-LSPs may be protected.
The detour S2L sub-LSPs may or may not share labels, depending on the The detour S2L sub-LSPs may or may not share labels, depending on the
detour path. Thus the set of outgoing labels and next-hops for a P2MP detour path. Thus the set of outgoing labels and next-hops for a P2MP
LSP that was using a single next-hop and label between the PLR and LSP that was using a single next-hop and label between the PLR and
next-hop before protection, may change once protection is triggerred. next-hop before protection, may change once protection is triggerred.
Its is recommended that the path specific method be used to identify Its is recommended that the path specific method be used to identify
a backup S2L sub-LSP. Hence the DETOUR object will be inserted in the a backup S2L sub-LSP. Hence the DETOUR object SHOULD be inserted in
backup Path message. A backup S2L sub-LSP MUST be treated as belong- the backup Path message. A backup S2L sub-LSP MUST be treated as
ing to a different P2MP tunnel instance than the one specified by the belonging to a different P2MP tunnel instance than the one specified
LSP-id. Furthermore multiple backup S2L sub-LSPs MUST be treated as by the LSP-id. Furthermore multiple backup S2L sub-LSPs MUST be
part of the same P2MP tunnel instance if they have the same LSP-id treated as part of the same P2MP tunnel instance if they have the
and the same DETOUR objects. Note that as specified in section 4 S2L same LSP-id and the same DETOUR objects. Note that as specified in
sub-LSPs between different P2MP tunnel instances use different section 4 S2L sub-LSPs between different P2MP tunnel instances use
labels. different labels.
If there is only one S2L sub-LSP in the Path message, the DETOUR If there is only one S2L sub-LSP in the Path message, the DETOUR
object applies to that sub-LSP. If there are multiple S2L sub-LSPs in object applies to that sub-LSP. If there are multiple S2L sub-LSPs in
the Path message the DETOUR applies to all the S2L sub-LSPs. the Path message the DETOUR applies to all the S2L sub-LSPs.
16. Support for LSRs that are not P2MP Capable 16. Support for LSRs that are not P2MP Capable
It may be that some LSRs in a network are capable of processing the It may be that some LSRs in a network are capable of processing the
P2MP extensions described in this document, but do not support P2MP P2MP extensions described in this document, but do not support P2MP
branching in the data plane. If such an LSR is requested to become a branching in the data plane. If such an LSR is requested to become a
branch LSR by a received Path message, it MUST respond with a PathErr branch LSR by a received Path message, it MUST respond with a PathErr
message carrying the Error Value "Routing Error" and Error Code message carrying the Error Code "Routing Error" and Error Value
"Unable to Branch". "Unable to Branch".
Its also conceivable that some LSRs, in a network deploying P2MP Its also conceivable that some LSRs, in a network deploying P2MP
capability, may not support the extensions described in this docu- capability, may not support the extensions described in this
ment. If a Path message for the establishment of a P2MP LSP reaches document. If a Path message for the establishment of a P2MP LSP
such an LSR it will reject it with a PathErr because it will not rec- reaches such an LSR it will reject it with a PathErr because it will
ognize the C-Type of the P2MP SESSION object. not recognize the C-Type of the P2MP SESSION object.
LSRs that do not support the P2MP extensions in this document may be LSRs that do not support the P2MP extensions in this document may be
included as transit LSRs by the use of LSP-stitching [LSP-STITCH] and included as transit LSRs by the use of LSP-stitching [LSP-STITCH] and
LSP-hierarchy [LSP-HIER]. Note that LSRs that are required to play LSP-hierarchy [RFC4206]. Note that LSRs that are required to play any
any other role in the network (ingress, branch or egress) MUST sup- other role in the network (ingress, branch or egress) MUST support
port the extensions defined in this document. the extensions defined in this document.
The use of LSP-stitching and LSP-hierarchy [LSP-HIER] allows to build The use of LSP-stitching and LSP-hierarchy [RFC4206] allows P2MP LSPs
P2MP LSPs in such an environment. A P2P LSP segment is signaled from to be built in such an environment. A P2P LSP segment is signaled
the previous P2MP capable hop of a legacy LSR to the next P2MP capa- from the last P2MP capable hop upstream of a legacy LSR to the first
ble hop. Of course this assumes that intermediate legacy LSRs are P2MP capable hop downstream of it. This assumes that intermediate
transit LSRs and cannot act as P2MP branch points. Transit LSRs along legacy LSRs are transit LSRs: they cannot act as P2MP branch points.
this LSP segment do not process control plane messages associated
with a P2MP LSP. Furthermore these LSRs also do not need to have P2MP Transit LSRs along this LSP segment do not process control plane
data plane capability as they only need to process data belonging to messages associated with the P2MP LSP. Furthermore, these transit
the P2P LSP segment. Hence these LSRs do not need to support P2MP LSRs also do not need to have P2MP data plane capabilities as they
MPLS. This P2P LSP segment is stitched to the incoming P2MP LSP. only need to process data belonging to the P2P LSP segment. Hence
After the P2P LSP segment is established the P2MP Path message is these transit LSRs do not need to support P2MP MPLS. This P2P LSP
sent to the next P2MP capable LSR as a directed Path message. The segment is stitched to the incoming P2MP LSP. After the P2P LSP
next P2MP capable LSR stitches the P2P LSP segment to the outgoing segment is established the P2MP Path message is sent to the next P2MP
P2MP LSP. capable LSR as a directed Path message. The next P2MP capable LSR
stitches the P2P LSP segment to the outgoing P2MP LSP.
In packet networks, the S2L sub-LSPs may be nested inside the outer In packet networks, the S2L sub-LSPs may be nested inside the outer
P2P LSP. Hence label stacking can be used to enable use of the same P2P LSP. Hence label stacking can be used to enable use of the same
LSP segment for multiple P2MP LSP. Stitching and nesting considera- LSP segment for multiple P2MP LSP. Stitching and nesting
tions and procedures are described further in [INT-REG]. considerations and procedures are described further in [INT-REG].
It may be an overhead for an operator to configure the P2P LSP seg- It may be an overhead for an operator to configure the P2P LSP
ments in advance, when it is desired to support legacy LSRs. It may segments in advance, when it is desired to support legacy LSRs. It
be desirable to do this dynamically. The ingress can use IGP exten- may be desirable to do this dynamically. The ingress can use IGP
sions to determine non P2MP capable LSRs [TE-NODE-CAP]. It can use extensions to determine non P2MP capable LSRs [TE-NODE-CAP]. It can
this information to compute S2L sub-LSP paths such that they avoid use this information to compute S2L sub-LSP paths such that they
these legacy LSRs. The explicit route object of a S2L sub-LSP path avoid these legacy LSRs. The explicit route object of a S2L sub-LSP
may contain loose hops if there are legacy LSRs along the path. The path may contain loose hops if there are legacy LSRs along the path.
corresponding explicit route contains a list of objects upto the P2MP The corresponding explicit route contains a list of objects upto the
capable LSR that is adjacent to a legacy LSR followed by a loose P2MP capable LSR that is adjacent to a legacy LSR followed by a loose
object with the address of the next P2MP capable LSR. The P2MP capa- object with the address of the next P2MP capable LSR. The P2MP
ble LSR expands the loose hop using its TED. When doing this it capable LSR expands the loose hop using its TED. When doing this it
determines that the loose hop expansion requires a P2P LSP to tunnel determines that the loose hop expansion requires a P2P LSP to tunnel
through the legacy LSR. If such a P2P LSP exists, it uses that P2P through the legacy LSR. If such a P2P LSP exists, it uses that P2P
LSP. Else it establishes the P2P LSP. The P2MP Path message is sent LSP. Else it establishes the P2P LSP. The P2MP Path message is sent
to the next P2MP capable LSR using non-adjacent signaling. The P2MP to the next P2MP capable LSR using non-adjacent signaling. The P2MP
capable LSR that initiates the non-adjacent signaling message to the capable LSR that initiates the non-adjacent signaling message to the
next P2MP capable LSR may have to employ a fast detection mechanism next P2MP capable LSR may have to employ a fast detection mechanism
such as [BFD] to the next P2MP capable LSR. such as [BFD] to the next P2MP capable LSR.
This may be needed for the directed Path message Head-End to use node This may be needed for the directed Path message Head-End to use node
protection FRR when the protected node is the directed Path message protection FRR when the protected node is the directed Path message
tail. tail.
Note that legacy LSRs along a P2P LSP segment cannot perform node Note that legacy LSRs along a P2P LSP segment cannot perform node
protection of the tail of the P2P LSP segment. protection of the tail of the P2P LSP segment.
17. Reduction in Control Plane Processing with LSP Hierarchy 17. Reduction in Control Plane Processing with LSP Hierarchy
It is possible to take advantage of LSP hierarchy [LSP-HIER] while It is possible to take advantage of LSP hierarchy [RFC4206] while
setting up P2MP LSP, as described in the previous section, to reduce setting up P2MP LSP, as described in the previous section, to reduce
control plane processing along transit LSRs that are P2MP capable. control plane processing along transit LSRs that are P2MP capable.
This is applicable only in environments where LSP hierarchy can be This is applicable only in environments where LSP hierarchy can be
used. Transit LSRs along a P2P LSP segment, being used by a P2MP LSP, used. Transit LSRs along a P2P LSP segment, being used by a P2MP LSP,
do not process control plane messages associated with the P2MP LSP. do not process control plane messages associated with the P2MP LSP.
Infact they are not aware of these messages as they are tunneled over Infact they are not aware of these messages as they are tunneled over
the P2P LSP segment. This reduces the amount of control plane pro- the P2P LSP segment. This reduces the amount of control plane
cessing required on these transit LSRs. processing required on these transit LSRs.
Note that the P2P LSP segments can be dynamically setup as described Note that the P2P LSPs be dynamically setup as described in the
in the previous section or preconfigured. For example in Figure 2, previous section or preconfigured. For example in Figure 2, PE1 can
PE1 can setup a P2P LSP to P1 and use that as a LSP segment. The Path setup a P2P LSP to P1 and use that as a LSP segment. The Path
messages for PE3 and PE4 can now be tunneled over the LSP segment. messages for PE3 and PE4 can now be tunneled over the LSP segment.
Thus P3 is not aware of the P2MP LSP and does not process the P2MP Thus P3 is not aware of the P2MP LSP and does not process the P2MP
control messages. control messages.
18. P2MP LSP Remerging and Cross-Over 18. P2MP LSP Remerging and Cross-Over
This section is currently under discussion between the authors and This section is currently under discussion between the authors and
will be updated in the next revision. will be updated in the next revision.
This section details the procedures for detecting and dealing with This section details the procedures for detecting and dealing with
skipping to change at page 33, line 34 skipping to change at page 35, line 23
(Make-before-break represents yet another similar but different case, (Make-before-break represents yet another similar but different case,
in that the incoming interface associated with the make-before-break in that the incoming interface associated with the make-before-break
P2MP LSP may be different than that associated with the original P2MP P2MP LSP may be different than that associated with the original P2MP
LSP. However, the two P2MP LSPs will be treated as distinct, but LSP. However, the two P2MP LSPs will be treated as distinct, but
related, LSPs because they will have different LSP ID field values in related, LSPs because they will have different LSP ID field values in
their SENDER_TEMPLATE objects.) their SENDER_TEMPLATE objects.)
18.1. Procedures 18.1. Procedures
When a node receives a Path message, it MUST check whether it has When a node receives a Path message, it MUST check whether it has
matching state for the P2MP LSP. Matching state is identified by com- matching state for the P2MP LSP. Matching state is identified by
paring the SESSION and SENDER_TEMPLATE objects in the received Path comparing the SESSION and SENDER_TEMPLATE objects in the received
message with the SESSION and SENDER_TEMPLATE objects of each locally Path message with the SESSION and SENDER_TEMPLATE objects of each
maintained P2MP LSP Path state. The P2MP ID, Tunnel ID, and Extended locally maintained P2MP LSP Path state. The P2MP ID, Tunnel ID, and
Tunnel ID in the SESSION Object and the sender address and LSP ID in Extended Tunnel ID in the SESSION Object and the sender address and
the SENDER_TEMPLATE object are used for the comparison. If the node LSP ID in the SENDER_TEMPLATE object are used for the comparison. If
has matching state and the incoming interface for the received Path the node has matching state and the incoming interface for the
message is different than the incoming interface of the matching P2MP received Path message is different than the incoming interface of the
LSP Path state, then the node MUST determine whether it is dealing matching P2MP LSP Path state, then the node MUST determine whether it
with dynamic LSP rerouting or re-merge/cross-over. is dealing with dynamic LSP rerouting or re-merge/cross-over.
Dynamic LSP rerouting is identified by checking whether there is any Dynamic LSP rerouting is identified by checking whether there is any
intersection between the set of SUB-LSP objects associated with the intersection between the set of SUB-LSP objects associated with the
matching P2MP LSP Path state and the set of SUB-LSP objects in the matching P2MP LSP Path state and the set of SUB-LSP objects in the
received Path message. If there is any intersection, then dynamic received Path message. If there is any intersection, then dynamic
re-routing has occurred. If there is no intersection between the two re-routing has occurred. If there is no intersection between the two
sets of SUB-LSP objects, then either re-merge or cross-over has sets of SUB-LSP objects, then either re-merge or cross-over has
occurred. (Note that in the case of dynamic LSP rerouting, Path mes- occurred. (Note that in the case of dynamic LSP rerouting, Path
sages for the non-intersecting members of set of SUB-LSPs associated messages for the non-intersecting members of set of SUB-LSPs
with the matching P2MP LSP Path state will be received subsequently associated with the matching P2MP LSP Path state will be received
on the new incoming interface.) subsequently on the new incoming interface.)
In order to identify the re-merge case, the node processing the In order to identify the re-merge case, the node processing the
received Path message MUST identify the outgoing interfaces associ- received Path message MUST identify the outgoing interfaces
ated with the matching P2MP Path state. Re-merge has occurred if associated with the matching P2MP Path state. Re-merge has occurred
there is any intersection between the set of outgoing interfaces if there is any intersection between the set of outgoing interfaces
associated with the matching P2MP LSP Path state and the set of out- associated with the matching P2MP LSP Path state and the set of
going interfaces in the received Path message. outgoing interfaces in the received Path message.
18.1.1. Re-Merge Procedures 18.1.1. Re-Merge Procedures
There are two approaches to dealing with re-merge case. In the There are two approaches to dealing with re-merge case. In the
first, the node detecting the re-merge case, i.e., the re-merge node, first, the node detecting the re-merge case, i.e., the re-merge node,
allows the re-merge case to persist but data from all but one incom- allows the re-merge case to persist but data from all but one
ing interface is dropped at the re-merge node. In the second, the incoming interface is dropped at the re-merge node. In the second,
re-merge node initiates the removal of the re-merge branch(es) via the re-merge node initiates the removal of the re-merge branch(es)
signaling. Which approach is used is a matter of local policy. A via signaling. Which approach is used is a matter of local policy.
node MUST support both approaches and MUST allow user configuration A node MUST support both approaches and MUST allow user configuration
of which approach is to be used. of which approach is to be used.
When configured to allow a re-merge case to persist, the re-merge When configured to allow a re-merge case to persist, the re-merge
node MUST validate consistency between the objects included the node MUST validate consistency between the objects included the
received Path message and the matching P2MP LSP Path state. Any received Path message and the matching P2MP LSP Path state. Any
inconsistencies MUST result in an appropriate PathErr message sent to inconsistencies MUST result in an appropriate PathErr message sent to
the previous hop of the received Path message. The error code is set the previous hop of the received Path message. The Error Code is set
to "Routing Problem" and the error value is set to "P2MP Re-Merge to "Routing Problem" and the Error Value is set to "P2MP Re-Merge
Parameter Mistmatch". Parameter Mistmatch".
If there are no inconsistencies, the node logically merges, from the If there are no inconsistencies, the node logically merges, from the
downstream perspective, the control state of incoming Path message downstream perspective, the control state of incoming Path message
with the matching P2MP LSP Path state. Specifically, procedures with the matching P2MP LSP Path state. Specifically, procedures
related to processing of messages received from upstream MUST NOT be related to processing of messages received from upstream MUST NOT be
modified from the upstream perspective; this includes refresh and modified from the upstream perspective; this includes refresh and
state timeout related processing. In addition to the standard state timeout related processing. In addition to the standard
upstream related procedures, the node MUST ensure that each object upstream related procedures, the node MUST ensure that each object
received from upstream is appropriately represented within the set of received from upstream is appropriately represented within the set of
Path messages sent downstream. For example, the received <S2L sub-LSP Path messages sent downstream. For example, the received <S2L sub-LSP
descriptor list> MUST be included in the set of outgoing Path mes- descriptor list> MUST be included in the set of outgoing Path
sages. If there are any NOTIFY_REQUEST request objects present, then messages. If there are any NOTIFY_REQUEST request objects present,
the procedures defined in Section 8 MUST be followed for both Path then the procedures defined in Section 8 MUST be followed for both
and Resv messages. Special processing is also required for Resv pro- Path and Resv messages. Special processing is also required for Resv
cessing. Specifically, any Resv message received from downstream processing. Specifically, any Resv message received from downstream
MUST be mapped into an outgoing Resv message that is sent to the pre- MUST be mapped into an outgoing Resv message that is sent to the
vious hop of the received Path message. In practice, this translates previous hop of the received Path message. In practice, this
to decomposing the complete <S2L sub-LSP descriptor list> into sub- translates to decomposing the complete <S2L sub-LSP descriptor list>
sets that match the incoming Path messages and then constructing an into sub-sets that match the incoming Path messages and then
outgoing Resv message for each incoming Path message. constructing an outgoing Resv message for each incoming Path message.
When configured to allow a re-merge case to persist, the re-merge When configured to allow a re-merge case to persist, the re-merge
node receives data associated with the P2MP LSP on multiple incoming node receives data associated with the P2MP LSP on multiple incoming
interfaces, but it may only send the data from one of these inter- interfaces, but it may only send the data from one of these
faces to its outgoing interfaces, i.e., the node MUST drop data from interfaces to its outgoing interfaces, i.e., the node MUST drop data
all but one incoming interface. This ensures that duplicate data is from all but one incoming interface. This ensures that duplicate
not sent on any outgoing interface. The mechanism used to select the data is not sent on any outgoing interface. The mechanism used to
incoming interface to use is implementation specific and is outside select the incoming interface to use is implementation specific and
the scope of this document. is outside the scope of this document.
When configured to correct the re-merge branch via signaling, the re- When configured to correct the re-merge branch via signaling, the re-
merge node MUST send a PathErr message corresponding to the received merge node MUST send a PathErr message corresponding to the received
Path message. The PathErr message MUST include all of the objects Path message. The PathErr message MUST include all of the objects
normally included in a PathErr message, as well as one or more SUB- normally included in a PathErr message, as well as one or more SUB-
LSP objects from the set of sub-LSPs associated with the matching LSP objects from the set of sub-LSPs associated with the matching
P2MP LSP Path state. A minimum of three SUB-LSP objects is RECOM- P2MP LSP Path state. A minimum of three SUB-LSP objects is
MENDED. This will allow the node that caused the re-merge to identify RECOMMENDED. This will allow the node that caused the re-merge to
the outgoing Path state associated with the valid portion of the P2MP identify the outgoing Path state associated with the valid portion of
LSP. The PathErr message MUST include the error code "Routing Prob- the P2MP LSP. The set of SUB-LSP objects in the received Path message
lem" and error value of "P2MP Remerge Detected". The node MAY set the MUST also be included. The PathErr message MUST include the Error
Path_State_Removed flag [RFC3473]. As is always the case, the Code "Routing Problem" and Error Value of "P2MP Remerge Detected".
PathErr message is sent to the previous hop of the received Path mes- The node MAY set the Path_State_Removed flag [RFC3473]. As is always
sage. the case, the PathErr message is sent to the previous hop of the
received Path message.
A node that receives a PathErr message that contains the error "Rout- A node that receives a PathErr message that contains the Error Value
ing Problem/P2MP Remerge Detected" MUST determine if it is the node "Routing Problem/P2MP Remerge Detected" MUST determine if it is the
that created the re-merge case. This is done by checking whether node that created the re-merge case. This is done by checking
there is any intersection between the set of SUB-LSP objects associ- whether there is any intersection between the set of SUB-LSP objects
ated with the matching P2MP LSP Path state and the set of SUB-LSP associated with the matching P2MP LSP Path state and the set of SUB-
objects in the received PathErr message. If there is, then the node LSP objects in the received PathErr message. If there is, then the
created the re-merge case. node created the re-merge case.
The node SHOULD remove the re-merge case by moving the SUB-LSP The node SHOULD remove the re-merge case by moving the SUB-LSP
objects included in the Path message associated with the received objects included in the Path message associated with the received
PathErr message to the outgoing interface associated with the match- PathErr message to the outgoing interface associated with the
ing P2MP LSP Path state. A trigger Path message for the moved SUB- matching P2MP LSP Path state. A trigger Path message for the moved
LSP objects is then sent via that outgoing interface. If the SUB-LSP objects is then sent via that outgoing interface. If the
received PathErr message did not have the Path_State_Removed flag received PathErr message did not have the Path_State_Removed flag
set, the node SHOULD send a PathTear via the outgoing interface asso- set, the node SHOULD send a PathTear via the outgoing interface
ciated with the re-merge branch. associated with the re-merge branch.
If use of a new outgoing interface violates one or more SERO con- If use of a new outgoing interface violates one or more SERO
straint, then a PathErr message containing the associated egresses constraint, then a PathErr message containing the associated egresses
and any identified SUB-LSP objects SHOULD be generated with the error and any identified SUB-LSP objects SHOULD be generated with the Error
code "Routing Problem" and error value of "ERO Resulted in Remerge". Code "Routing Problem" and Error Value of "ERO Resulted in Remerge".
The only case where this process will fail is when all the listed The only case where this process will fail is when all the listed
SUB-LSP objects are deleted prior to the PathErr message propagating SUB-LSP objects are deleted prior to the PathErr message propagating
to the ingress. In this case, the whole process will be corrected on to the ingress. In this case, the whole process will be corrected on
the next (refresh or trigger) transmission of the offending Path mes- the next (refresh or trigger) transmission of the offending Path
sage. message.
19. New and Updated Message Objects 19. New and Updated Message Objects
This section presents the RSVP object formats as modified by this This section presents the RSVP object formats as modified by this
document. document.
19.1. SESSION Object 19.1. SESSION Object
A P2MP LSP SESSION object is used. This object uses the existing A P2MP LSP SESSION object is used. This object uses the existing
SESSION C-Num. New C-Types are defined to accommodate a logical P2MP SESSION C-Num. New C-Types are defined to accommodate a logical P2MP
destination identifier of the P2MP Tunnel. This SESSION object has a destination identifier of the P2MP Tunnel. This SESSION object has a
similar structure as the existing point to point RSVP-TE SESSION similar structure as the existing point to point RSVP-TE SESSION
object. However the destination address is set to the P2MP ID object. However the destination address is set to the P2MP ID
instead of the unicast Tunnel Endpoint address. All S2L sub-LSPs part instead of the unicast Tunnel Endpoint address. All S2L sub-LSPs that
of the same P2MP LSP share the same SESSION object. This SESSION are part of the same P2MP LSP share the same SESSION object. This
object identifies the P2MP Tunnel. SESSION object identifies the P2MP Tunnel.
The combination of the SESSION object, the SENDER_TEMPLATE object and The combination of the SESSION object, the SENDER_TEMPLATE object and
the <S2L_SUB_LSP> object, identifies each S2L sub-LSP. This follows the <S2L_SUB_LSP> object, identifies each S2L sub-LSP. This follows
the existing P2P RSVP-TE notion of using the SESSION object for iden- the existing P2P RSVP-TE notion of using the SESSION object for
tifying a P2P Tunnel which in turn can contain multiple LSPs, each identifying a P2P Tunnel which in turn can contain multiple LSPs,
distinguished by a unique SENDER_TEMPLATE object. each distinguished by a unique SENDER_TEMPLATE object.
19.1.1. P2MP LSP Tunnel IPv4 SESSION Object 19.1.1. P2MP LSP Tunnel IPv4 SESSION Object
Class = SESSION, P2MP_LSP_TUNNEL_IPv4 C-Type = TBA Class = SESSION, P2MP_LSP_TUNNEL_IPv4 C-Type = 13
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| P2MP ID | | P2MP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MUST be zero | Tunnel ID | | MUST be zero | Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID | | Extended Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 37, line 28 skipping to change at page 39, line 21
all zeros. Ingress nodes that wish to narrow the scope of a all zeros. Ingress nodes that wish to narrow the scope of a
SESSION to the ingress-PID pair may place their IPv4 address SESSION to the ingress-PID pair may place their IPv4 address
here as a globally unique identifier [RFC3209]. here as a globally unique identifier [RFC3209].
19.1.2. P2MP LSP Tunnel IPv6 SESSION Object 19.1.2. P2MP LSP Tunnel IPv6 SESSION Object
This is same as the P2MP IPv4 LSP SESSION Object with the difference This is same as the P2MP IPv4 LSP SESSION Object with the difference
that the extended tunnel ID may be set to a 16 byte identifier that the extended tunnel ID may be set to a 16 byte identifier
[RFC3209]. [RFC3209].
Class = SESSION, P2MP_LSP_TUNNEL_IPv4 C-Type = 14
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| P2MP ID | | P2MP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MUST be zero | Tunnel ID | | MUST be zero | Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID (16 bytes) | | Extended Tunnel ID (16 bytes) |
| | | |
| ....... | | ....... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
19.2. SENDER_TEMPLATE object 19.2. SENDER_TEMPLATE object
The SENDER_TEMPLATE object contains the ingress-LSR source address. The SENDER_TEMPLATE object contains the ingress-LSR source address.
LSP ID can be can be changed to allow a sender to share resources LSP ID can be can be changed to allow a sender to share resources
with itself. Thus multiple instances of the P2MP tunnel can be cre- with itself. Thus multiple instances of the P2MP tunnel can be
ated, each with a different LSP ID. The instances can share resources created, each with a different LSP ID. The instances can share
with each other, but use different labels. The S2L sub-LSPs corre- resources with each other, but use different labels. The S2L sub-LSPs
sponding to a particular instance use the same LSP ID. corresponding to a particular instance use the same LSP ID.
As described in section 4.2 it is necessary to distinguish different As described in section 4.2 it is necessary to distinguish different
Path messages that are used to signal state for the same P2MP LSP by Path messages that are used to signal state for the same P2MP LSP by
using a <Sub-Group ID Originator ID, Sub-Group ID> tuple. The using a <Sub-Group ID Originator ID, Sub-Group ID> tuple. The
SENDER_TEMPLATE object is modified to carry this information as shown SENDER_TEMPLATE object is modified to carry this information as shown
below. below.
19.2.1. P2MP LSP Tunnel IPv4 SENDER_TEMPLATE Object 19.2.1. P2MP LSP Tunnel IPv4 SENDER_TEMPLATE Object
Class = SENDER_TEMPLATE, P2MP_LSP_TUNNEL_IPv4 C-Type = TBA Class = SENDER_TEMPLATE, P2MP_LSP_TUNNEL_IPv4 C-Type = 12
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address | | IPv4 tunnel sender address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | LSP ID | | Reserved | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Group Originator ID | | Sub-Group Originator ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 39, line 7 skipping to change at page 40, line 41
An identifier of a Path message used to differentiate An identifier of a Path message used to differentiate
multiple Path messages that signal state for the same P2MP multiple Path messages that signal state for the same P2MP
LSP. This may be seen as identifying a group of one or more LSP. This may be seen as identifying a group of one or more
egress nodes targeted by this Path message. egress nodes targeted by this Path message.
LSP ID LSP ID
See [RFC3209] See [RFC3209]
19.2.2. P2MP LSP Tunnel IPv6 SENDER_TEMPLATE Object 19.2.2. P2MP LSP Tunnel IPv6 SENDER_TEMPLATE Object
Class = SENDER_TEMPLATE, P2MP_LSP_TUNNEL_IPv6 C-Type = TBA Class = SENDER_TEMPLATE, P2MP_LSP_TUNNEL_IPv6 C-Type = 13
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
+ + + +
| IPv6 tunnel sender address | | IPv6 tunnel sender address |
+ + + +
| (16 bytes) | | (16 bytes) |
+ + + +
skipping to change at page 39, line 43 skipping to change at page 41, line 31
IPv6 tunnel sender address IPv6 tunnel sender address
See [RFC3209] See [RFC3209]
Sub-Group Originator ID Sub-Group Originator ID
The Sub-Group Originator ID is set to the IPv6 TE Router ID The Sub-Group Originator ID is set to the IPv6 TE Router ID
of the LSR that originates the Path message. This is either of the LSR that originates the Path message. This is either
the ingress LSR or a LSR which re-originates the Path the ingress LSR or a LSR which re-originates the Path
message with its own Sub-Group Originator ID. message with its own Sub-Group Originator ID.
Sub-Group ID Sub-Group ID
As above in section 19.2.2. As above in section 19.2.1.
LSP ID LSP ID
See [RFC3209] See [RFC3209]
19.3. <S2L_SUB_LSP> Object 19.3. <S2L_SUB_LSP> Object
A new <S2L_SUB_LSP> object identifies a particular S2L sub-LSP A new <S2L_SUB_LSP> object identifies a particular S2L sub-LSP
belonging to the P2MP LSP. belonging to the P2MP LSP.
19.3.1. <S2L_SUB_LSP> IPv4 Object 19.3.1. <S2L_SUB_LSP> IPv4 Object
SUB_LSP Class = 50, S2L_SUB_LSP_IPv4 C-Type = TBA SUB_LSP Class = 50, S2L_SUB_LSP_IPv4 C-Type = 1
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 S2L Sub-LSP destination address | | IPv4 S2L Sub-LSP destination address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
IPv4 Sub-LSP destination address IPv4 Sub-LSP destination address
IPv4 address of the S2L sub-LSP destination. IPv4 address of the S2L sub-LSP destination.
19.3.2. <S2L_SUB_LSP> IPv6 Object 19.3.2. <S2L_SUB_LSP> IPv6 Object
SUB_LSP Class = 50, S2L_SUB_LSP_IPv6 C-Type = TBA SUB_LSP Class = 50, S2L_SUB_LSP_IPv6 C-Type = 2
This is same as the S2L IPv4 Sub-LSP object, with the difference that This is same as the S2L IPv4 Sub-LSP object, with the difference that
the destination address is a 16 byte IPv6 address. the destination address is a 16 byte IPv6 address.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 S2L Sub-LSP destination address (16 bytes) | | IPv6 S2L Sub-LSP destination address (16 bytes) |
| .... | | .... |
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
19.4. FILTER_SPEC Object 19.4. FILTER_SPEC Object
The FILTER_SPEC object is canonical to the P2MP SENDER_TEMPLATE The FILTER_SPEC object is canonical to the P2MP SENDER_TEMPLATE
object. object.
19.4.1. P2MP LSP_IPv4 FILTER_SPEC Object 19.4.1. P2MP LSP_IPv4 FILTER_SPEC Object
Class = FILTER SPEC, P2MP LSP_IPv4 C-Type = TBA Class = FILTER SPEC, P2MP LSP_IPv4 C-Type = 12
The format of the P2MP LSP_IPv4 FILTER_SPEC object is identical to The format of the P2MP LSP_IPv4 FILTER_SPEC object is identical to
the P2MP LSP_IPv4 SENDER_TEMPLATE object. the P2MP LSP_IPv4 SENDER_TEMPLATE object.
19.4.2. P2MP LSP_IPv4 FILTER_SPEC Object 19.4.2. P2MP LSP_IPv4 FILTER_SPEC Object
Class = FILTER SPEC, P2MP LSP_IPv6 C-Type = TBA Class = FILTER SPEC, P2MP LSP_IPv6 C-Type = 13
The format of the P2MP LSP_IPv6 FILTER_SPEC object is identical to The format of the P2MP LSP_IPv6 FILTER_SPEC object is identical to
the P2MP LSP_IPv6 SENDER_TEMPLATE object. the P2MP LSP_IPv6 SENDER_TEMPLATE object.
19.5. P2MP SECONDARY_EXPLICIT_ROUTE Object (SERO) 19.5. P2MP SECONDARY_EXPLICIT_ROUTE Object (SERO)
The P2MP Secondary Explicit Route Object (SERO) is defined as identi- The P2MP SECONDARY_EXPLICIT_ROUTE Object (SERO) is defined as
cal to the ERO. The class of the P2MP SERO is the same as the SERO identical to the ERO. The class of the P2MP SERO is the same as the
defined in [RECOVERY]. The P2MP SERO uses a new C-Type = 2. The sub- SERO defined in [RECOVERY]. The P2MP SERO uses a new C-Type = 2. The
objects are identical to those defined for the ERO. sub-objects are identical to those defined for the ERO.
19.6. P2MP SECONDARY_RECORD_ROUTE Object (SRRO) 19.6. P2MP SECONDARY_RECORD_ROUTE Object (SRRO)
The P2MP SECONDARY_RECORD_ROUTE Object (SRRO) is defined as identical The P2MP SECONDARY_RECORD_ROUTE Object (SRRO) is defined as identical
to the ERO. The class of the P2MP SRRO is the same as the SRRO to the ERO. The class of the P2MP SRRO is the same as the SRRO
defined in [RECOVERY]. The P2MP SRRO uses a new C-Type = 2. The sub- defined in [RECOVERY]. The P2MP SRRO uses a new C-Type = 2. The sub-
objects are identical to those defined for the RRO. objects are identical to those defined for the RRO.
20. IANA Considerations 20. IANA Considerations
skipping to change at page 42, line 37 skipping to change at page 44, line 20
Class Name = SECONDARY_EXPLICIT_ROUTE Class Name = SECONDARY_EXPLICIT_ROUTE
C-Type C-Type
2 P2MP SECONDARY_EXPLICIT_ROUTE C-Type 2 P2MP SECONDARY_EXPLICIT_ROUTE C-Type
Class Name = SECONDARY_RECORD_ROUTE Class Name = SECONDARY_RECORD_ROUTE
C-Type C-Type
2 P2MP_SECONDARY_RECORD_ROUTE C-Type 2 P2MP_SECONDARY_RECORD_ROUTE C-Type
20.3. New Error Codes 20.3. New Error Values
Four new Error Codes are defined for use with the Error Value "Rout- Four new Error Values are defined for use with the Error Code
ing Problem". IANA is requested to assign values. "Routing Problem". IANA is requested to assign values.
The Error Code "Unable to Branch" indicates that a P2MP branch cannot The Error Value "Unable to Branch" indicates that a P2MP branch
be formed by the reporting LSR. IANA is requested to assign value 23 cannot be formed by the reporting LSR. IANA is requested to assign
to this Error Code. value 23 to this Error Value.
The Error Code "Unsupported LSP Integrity" indicates that a P2MP The Error Value "Unsupported LSP Integrity" indicates that a P2MP
branch does not support the requested LSP integrity function. IANA is branch does not support the requested LSP integrity function. IANA is
requested to assign value 24 to this Error Code. requested to assign value 24 to this Error Value.
The Error Code "P2MP Remerge Detected" indicates that a node has The Error Value "P2MP Remerge Detected" indicates that a node has
detected remerge. IANA is requested to assign value 25 to this Error detected remerge. IANA is requested to assign value 25 to this Error
Code. Value.
The Error Value "P2MP Re-Merge Parameter Mismatch" is described in
section 18. IANA is requested to assign value 26 to this Error Value.
The Error Value "ERO Resulted in Remerge" is described in section 18.
IANA is requested to assign value 27 to this Error Value.
20.4. LSP Attributes Flags 20.4. LSP Attributes Flags
IANA has been asked to manage the space of flags in the Attibutes IANA has been asked to manage the space of flags in the Attibutes
Flags TLV carried in the LSP_ATTRIBUTES Object [LSP-ATTRIB]. This Flags TLV carried in the LSP_REQUIRED_ATTRIBUTES Object [LSP-ATTRIB].
document defines two new flags as follows: This document defines a new flag as follows:
Suggested Bit Number: 3 Suggested Bit Number: 3
Meaning: LSP Integrity Required Meaning: LSP Integrity Required
Used in Attributes Flags on Path: Yes Used in Attributes Flags on Path: Yes
Used in Attributes Flags on Resv: No Used in Attributes Flags on Resv: No
Used in Attributes Flags on RRO: No Used in Attributes Flags on RRO: No
Referenced Section of this Doc: 10 Referenced Section of this Doc: 10
21. Security Considerations 21. Security Considerations
This document does not introduce any new security issues. The secu- This document does not introduce any new security issues. The
rity issues identified in [RFC3209] and [RFC3473] are still relevant. security issues identified in [RFC3209] and [RFC3473] are still
relevant.
22. Acknowledgements 22. Acknowledgements
This document is the product of many people. The contributors are This document is the product of many people. The contributors are
listed in Section 27.2. listed in Section 27.2.
Thanks to Yakov Rekhter, Der-Hwa Gan, Arthi Ayyanger and Nischal Thanks to Yakov Rekhter, Der-Hwa Gan, Arthi Ayyanger and Nischal
Sheth for their suggestions and comments. Thanks also to Dino Farni- Sheth for their suggestions and comments. Thanks also to Dino
nacci for his comments. Farninacci for his comments.
23. Appendix 23. Appendix
23.1. Example 23.1. Example
Following is one example of setting up a P2MP LSP using the proce- Following is one example of setting up a P2MP LSP using the
dures described in this document. procedures described in this document.
Source 1 (S1) Source 1 (S1)
| |
PE1 PE1
| | | |
|L5 | |L5 |
P3 | P3 |
| | | |
L3 |L1 |L2 L3 |L1 |L2
R2----PE3--P1 P2---PE2--Receiver 1 (R1) R2----PE3--P1 P2---PE2--Receiver 1 (R1)
skipping to change at page 44, line 40 skipping to change at page 46, line 38
e) PE1 establishes the S2L sub-LSP to PE3 along <PE1, P3, P1, PE3> e) PE1 establishes the S2L sub-LSP to PE3 along <PE1, P3, P1, PE3>
f) PE1 computes the P2P path to reach PE4 when it discovers PE4. This f) PE1 computes the P2P path to reach PE4 when it discovers PE4. This
path is computed to share the same links where possible with the sub- path is computed to share the same links where possible with the sub-
LSPs to PE2 and PE3 as they belong to the same P2MP session. LSPs to PE2 and PE3 as they belong to the same P2MP session.
g) PE1 signals the Path message for PE4 sub-LSP along <PE1, P3, P1, g) PE1 signals the Path message for PE4 sub-LSP along <PE1, P3, P1,
PE4> PE4>
e) P1 receives a Resv message from PE4 with label L4. It had previ- e) P1 receives a Resv message from PE4 with label L4. It had
ously received a Resv message from PE3 with label L3. It had allo- previously received a Resv message from PE3 with label L3. It had
cated a label L1 for the sub-LSP to PE3. It uses the same label and allocated a label L1 for the sub-LSP to PE3. It uses the same label
sends the Resv messages to P3. Note that it may send only one Resv and sends the Resv messages to P3. Note that it may send only one
message with multiple flow descriptors in the flow descriptor list. Resv message with multiple flow descriptors in the flow descriptor
If this is the case and FF style is used, the FF flow descriptor will list. If this is the case and FF style is used, the FF flow
contain the S2L sub-LSP descriptor list with two entries: one for PE4 descriptor will contain the S2L sub-LSP descriptor list with two
and the other for PE3. For SE style, the SE filter spec will contain entries: one for PE4 and the other for PE3. For SE style, the SE
this S2L sub-LSP descriptor list. P1 also creates a label mapping of filter spec will contain this S2L sub-LSP descriptor list. P1 also
(L1 -> {L3, L4}). P3 uses the existing label L5 and sends the Resv creates a label mapping of (L1 -> {L3, L4}). P3 uses the existing
message to PE1, with label L5. It reuses the label mapping of {L5 -> label L5 and sends the Resv message to PE1, with label L5. It reuses
L1}. the label mapping of {L5 -> L1}.
24. References 24. References
24.1. Normative References 24.1. Normative References
[LSP-HIER] K. Kompella, Y. Rekhter, "LSP Hierarchy with Generalized [RFC4206] K. Kompella, Y. Rekhter, "LSP Hierarchy with Generalized
MPLS TE", draft-ietf-mpls-lsp-hierarchy-08.txt, work in MPLS TE" [RFC4206]
progress.
[LSP-ATTR] A. Farrel, et. al. , "Encoding of [LSP-ATTR] A. Farrel, et. al. , "Encoding of
Attributes for Multiprotocol Label Switching (MPLS) Attributes for Multiprotocol Label Switching (MPLS)
Label Switched Path (LSP) Establishment Using RSVP-TE", Label Switched Path (LSP) Establishment Using RSVP-TE",
draft-ietf-mpls-rsvpte-attributes-05.txt, March 2004, draft-ietf-mpls-rsvpte-attributes-05.txt, March 2004,
work in progress. work in progress.
[RFC3209] D. Awduche, L. Berger, D. Gan, T. Li, V. Srinivasan, [RFC3209] D. Awduche, L. Berger, D. Gan, T. Li, V. Srinivasan,
G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels",
RFC3209, December 2001, work in progress. RFC3209, December 2001, work in progress.
skipping to change at page 46, line 7 skipping to change at page 47, line 52
Label Switching Architecture", RFC 3031, January 2001, work in Label Switching Architecture", RFC 3031, January 2001, work in
progress. progress.
[RFC4090] P. Pan, G. Swallow, A. Atlas (Editors), "Fast Reroute Extensions [RFC4090] P. Pan, G. Swallow, A. Atlas (Editors), "Fast Reroute Extensions
to RSVP-TE for LSP Tunnels", work in progress. to RSVP-TE for LSP Tunnels", work in progress.
[RFC3477] K. Kompella, Y. Rekther, "Signalling Unnumbered Links in [RFC3477] K. Kompella, Y. Rekther, "Signalling Unnumbered Links in
Resource ReSerVation Protocol - Traffic Engineering (RSVP-TE)", Resource ReSerVation Protocol - Traffic Engineering (RSVP-TE)",
work in progress . work in progress .
[P2MP-REQ] S. Yasukawa, Editor "Signaling Requirements for [RFC4461] S. Yasukawa, Editor "Signaling Requirements for
Point-to-Multipoint Traffic Engineered MPLS LSPs", Point-to-Multipoint Traffic Engineered MPLS LSPs", RFC4461.
draft-ietf-mpls-p2mp-sig-requirement-02.txt, work in progress.
[RECOVERY] "GMPLS Based Segment Recovery", [RECOVERY] "GMPLS Based Segment Recovery",
draft-ietf-ccamp-gmpls-segment-recovery-02.txt draft-ietf-ccamp-gmpls-segment-recovery-02.txt
24.2. Informative References 24.2. Informative References
[BFD] D. Katz, D. Ward, "Bidirectional Forwarding Detection", [BFD] D. Katz, D. Ward, "Bidirectional Forwarding Detection",
draft-katz-ward-bfd-01.txt, work in progress. draft-ietf-bfd-02.txt, work in progress.
[BFD-MPLS] R. Aggarwal, K. Kompella, T. Nadeau, G. Swallow, "BFD for MPLS [BFD-MPLS] R. Aggarwal, K. Kompella, T. Nadeau, G. Swallow, "BFD for MPLS
LSPs", draft-ietf-bfd-mpls-00.txt, work in progress. LSPs", draft-ietf-bfd-mpls-01.txt, work in progress.
[IPR-1] Bradner, S., "IETF Rights in Contributions", BCP 78, [IPR-1] Bradner, S., "IETF Rights in Contributions", BCP 78,
RFC 3667, February 2004, work in progress. RFC 3667, February 2004, work in progress.
[IPR-2] Bradner, S., Ed., "Intellectual Property Rights in IETF [IPR-2] Bradner, S., Ed., "Intellectual Property Rights in IETF
Technology", BCP 79, RFC 3668, February 2004, work in progress. Technology", BCP 79, RFC 3668, February 2004, work in progress.
[INT-REG] JP Vasseur, A. Ayyangar, "Inter-area and Inter-AS MPLS Traffic [INT-REG] A. Farrel, J.P. Vasseur, and A. Ayyangar, "A Framework for
Engineering", draft-vasseur-ccamp-inter-area-as-te-00.txt, Inter-Domain MPLS Traffic Engineering",
work in progress. draft-ietf-ccamp-inter-domain-framework-04.txt, work in
progress.
[RFC2209] R. Braden, L. Zhang, "Resource Reservation Protocol (RSVP) [RFC2209] R. Braden, L. Zhang, "Resource Reservation Protocol (RSVP)
Version 1 Message Processing Rules", RFC 2209, work in progress. Version 1 Message Processing Rules", RFC 2209, work in progress.
[LSP-STITCH] A. Ayyanger, J.P. Vasseur, "Label Switched Path Stitching [LSP-STITCH] A. Ayyanger, J.P. Vasseur, "Label Switched Path Stitching
with Generalized MPLS Traffic Engineering", with Generalized MPLS Traffic Engineering",
draft-ietf-ccamp-lsp-stitching-00.txt, April 2005 draft-ietf-ccamp-lsp-stitching-00.txt, April 2005
work in progress work in progress
[TE-NODE-CAP] JP Vasseur, JL Le Roux, et al. "Routing extensions for [TE-NODE-CAP] JP Vasseur, JL Le Roux, et al. "Routing extensions for
skipping to change at page 47, line 32 skipping to change at page 49, line 32
Dimitri Papadimitriou Dimitri Papadimitriou
Alcatel Alcatel
Francis Wellesplein 1, Francis Wellesplein 1,
B-2018 Antwerpen, Belgium B-2018 Antwerpen, Belgium
Phone: +32 3 240-8491 Phone: +32 3 240-8491
Email: Dimitri.Papadimitriou@alcatel.be Email: Dimitri.Papadimitriou@alcatel.be
25.2. Contributor Information 25.2. Contributor Information
John Drake John Drake
Calient Networks Boeing
Email: jdrake@calient.net Email: john.E.Drake2@boeing.com
Alan Kullberg Alan Kullberg
Motorola Computer Group Motorola Computer Group
120 Turnpike Road 1st Floor 120 Turnpike Road 1st Floor
Southborough, MA 01772 Southborough, MA 01772
EMail: alan.kullberg@motorola.com EMail: alan.kullberg@motorola.com
Lou Berger Lou Berger
Movaz Networks, Inc. Movaz Networks, Inc.
7926 Jones Branch Drive 7926 Jones Branch Drive
skipping to change at page 50, line 16 skipping to change at page 52, line 16
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights this document or the extent to which any license under such rights
might or might not be available; nor does it represent that it has might or might not be available; nor does it represent that it has
made any independent effort to identify any such rights. Information made any independent effort to identify any such rights. Information
on the procedures with respect to rights in RFC documents can be on the procedures with respect to rights in RFC documents can be
found in BCP 78 and BCP 79. found in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat and any assur- Copies of IPR disclosures made to the IETF Secretariat and any
ances of licenses to be made available, or the result of an attempt assurances of licenses to be made available, or the result of an
made to obtain a general license or permission for the use of such attempt made to obtain a general license or permission for the use of
proprietary rights by implementers or users of this specification can such proprietary rights by implementers or users of this
be obtained from the IETF on-line IPR repository at specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr. http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at ietf- this standard. Please address the information to the IETF at ietf-
ipr@ietf.org. ipr@ietf.org.
27. Full Copyright Statement 27. Full Copyright Statement
Copyright (C) The Internet Society (2005). This document is subject Copyright (C) The Internet Society (2006). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights. except as set forth therein, the authors retain all their rights.
This document and the information contained herein are provided on an This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFOR- INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
MATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
28. Acknowledgement 28. Acknowledgement
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is currently provided by the
Internet Society. Internet Society.
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