draft-ietf-teas-p2mp-loose-path-reopt-07.txt | draft-ietf-teas-p2mp-loose-path-reopt-08.txt | |||
---|---|---|---|---|
TEAS Working Group T. Saad, Ed. | TEAS Working Group T. Saad, Ed. | |||
Internet-Draft R. Gandhi, Ed. | Internet-Draft R. Gandhi, Ed. | |||
Intended status: Standards Track Z. Ali | Intended status: Standards Track Z. Ali | |||
Expires: April 27, 2017 Cisco Systems, Inc. | Expires: June 11, 2017 Cisco Systems, Inc. | |||
R. Venator | R. Venator | |||
Defense Information Systems Agency | Defense Information Systems Agency | |||
Y. Kamite | Y. Kamite | |||
NTT Communications Corporation | NTT Communications Corporation | |||
October 24, 2016 | December 8, 2016 | |||
RSVP Extensions For Re-optimization of Loosely Routed | RSVP Extensions For Re-optimization of Loosely Routed | |||
Point-to-Multipoint Traffic Engineering Label Switched Paths (LSPs) | Point-to-Multipoint Traffic Engineering Label Switched Paths (LSPs) | |||
draft-ietf-teas-p2mp-loose-path-reopt-07 | draft-ietf-teas-p2mp-loose-path-reopt-08 | |||
Abstract | Abstract | |||
Re-optimization of a Point-to-Multipoint (P2MP) Traffic Engineered | Re-optimization of a Point-to-Multipoint (P2MP) Traffic Engineered | |||
(TE) Label Switched Path (LSP) may be triggered based on the need to | (TE) Label Switched Path (LSP) may be triggered based on the need to | |||
re-optimize an individual source-to-leaf (S2L) sub-LSP or a set of | re-optimize an individual source-to-leaf (S2L) sub-LSP or a set of | |||
S2L sub-LSPs, both using Sub-Group-Based Re-optimization method, or | S2L sub-LSPs, both using Sub-Group-Based Re-optimization method, or | |||
the entire P2MP-TE LSP tree using the Make-Before-Break (MBB) method. | the entire P2MP-TE LSP tree using the Make-Before-Break (MBB) method. | |||
Mechanisms that facilitate path re-optimization of loosely routed | This document discusses the application of the existing mechanisms | |||
Point-to-Point (P2P) TE LSPs include a method for the ingress node to | for path re-optimization of loosely routed Point-to-Point (P2P) TE | |||
trigger a new path re-evaluation request and a method for the mid- | LSPs to the P2MP-TE LSPs, identifies issues in doing so and defines | |||
point node to notify availability of a preferred path. This document | procedures to address them. When re-optimizing a large number of S2L | |||
discusses the application of these mechanisms to the re-optimization | ||||
of loosely routed P2MP-TE LSPs, identifies issues in doing so and | ||||
proposes procedures to address them. | ||||
This document defines Resource Reservation Protocol (RSVP) signaling | ||||
extensions to allow the ingress node of a loosely routed P2MP-TE LSP | ||||
to request the re-evaluation of the LSP tree downstream of the node, | ||||
and a mid-point node to notify to the ingress node that a preferable | ||||
tree for the P2MP-TE LSP exists. For re-optimizing a group of S2L | ||||
sub-LSPs in a tree using the Sub-Group-Based Re-optimization method, | sub-LSPs in a tree using the Sub-Group-Based Re-optimization method, | |||
an S2L sub-LSP descriptor list can be used to signal one or more S2L | the S2L sub-LSP descriptor list may need to be semantically | |||
sub-LSPs in an RSVP message. This RSVP message may need to be | fragmented. This document defines the notion of a fragment | |||
semantically fragmented when large number of S2L sub-LSPs are added | identifier to help recipient nodes unambiguously reconstruct the | |||
to the descriptor list. This document introduces the notion of a | fragmented S2L sub-LSP descriptor list. | |||
fragment identifier to help recipient nodes unambiguously reconstruct | ||||
the fragmented S2L sub-LSP descriptor list. | ||||
Status of this Memo | Status of this Memo | |||
This Internet-Draft is submitted in full conformance with the | This Internet-Draft is submitted in full conformance with the | |||
provisions of BCP 78 and BCP 79. | provisions of BCP 78 and BCP 79. | |||
Internet-Drafts are working documents of the Internet Engineering | Internet-Drafts are working documents of the Internet Engineering | |||
Task Force (IETF). Note that other groups may also distribute | Task Force (IETF). Note that other groups may also distribute | |||
working documents as Internet-Drafts. The list of current Internet- | working documents as Internet-Drafts. The list of current Internet- | |||
Drafts is at http://datatracker.ietf.org/drafts/current/. | Drafts is at http://datatracker.ietf.org/drafts/current/. | |||
skipping to change at page 3, line 10 ¶ | skipping to change at page 3, line 10 ¶ | |||
to this document. Code Components extracted from this document must | to this document. Code Components extracted from this document must | |||
include Simplified BSD License text as described in Section 4.e of | include Simplified BSD License text as described in Section 4.e of | |||
the Trust Legal Provisions and are provided without warranty as | the Trust Legal Provisions and are provided without warranty as | |||
described in the Simplified BSD License. | described in the Simplified BSD License. | |||
Table of Contents | Table of Contents | |||
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 | 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 | |||
2. Conventions Used in This Document . . . . . . . . . . . . . . 4 | 2. Conventions Used in This Document . . . . . . . . . . . . . . 4 | |||
2.1. Key Word Definitions . . . . . . . . . . . . . . . . . . . 4 | 2.1. Key Word Definitions . . . . . . . . . . . . . . . . . . . 4 | |||
2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 4 | 2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 5 | |||
2.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5 | 2.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5 | |||
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 | 3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 | |||
3.1. Loosely Routed Inter-domain P2MP-TE LSP Tree . . . . . . . 6 | 3.1. Loosely Routed Inter-domain P2MP-TE LSP Tree . . . . . . . 6 | |||
3.2. Existing Mechanism For Tree-Based P2MP-TE LSP | 3.2. Existing Mechanism For Tree-Based P2MP-TE LSP | |||
Re-optimization . . . . . . . . . . . . . . . . . . . . . 6 | ||||
3.3. Existing Mechanism For Sub-Group-Based P2MP-TE LSP | ||||
Re-optimization . . . . . . . . . . . . . . . . . . . . . 7 | Re-optimization . . . . . . . . . . . . . . . . . . . . . 7 | |||
4. Signaling Procedure For Loosely Routed P2MP-TE LSP | 3.3. Existing Mechanism For Sub-Group-Based P2MP-TE LSP | |||
Re-optimization . . . . . . . . . . . . . . . . . . . . . . . 8 | Re-optimization . . . . . . . . . . . . . . . . . . . . . 8 | |||
4.1. Tree-Based Re-optimization . . . . . . . . . . . . . . . . 8 | 4. Signaling Extensions For Loosely Routed P2MP-TE LSP | |||
Re-optimization . . . . . . . . . . . . . . . . . . . . . . . 9 | ||||
4.1. Tree-Based Re-optimization . . . . . . . . . . . . . . . . 9 | ||||
4.2. Sub-Group-Based Re-optimization Using Fragment | 4.2. Sub-Group-Based Re-optimization Using Fragment | |||
Identifier . . . . . . . . . . . . . . . . . . . . . . . . 9 | Identifier . . . . . . . . . . . . . . . . . . . . . . . . 10 | |||
5. Message and Object Definitions . . . . . . . . . . . . . . . . 11 | 5. Message and Object Definitions . . . . . . . . . . . . . . . . 11 | |||
5.1. P2MP-TE Tree Re-evaluation Request Flag . . . . . . . . . 11 | 5.1. P2MP-TE Tree Re-evaluation Request Flag . . . . . . . . . 11 | |||
5.2. Preferable P2MP-TE Tree Exists Path Error Sub-code . . . . 11 | 5.2. Preferable P2MP-TE Tree Exists Path Error Sub-code . . . . 11 | |||
5.3. Fragment Identifier For S2L sub-LSP Descriptor . . . . . . 11 | 5.3. Fragment Identifier For S2L sub-LSP Descriptor . . . . . . 12 | |||
6. Compatibility . . . . . . . . . . . . . . . . . . . . . . . . 12 | 6. Compatibility . . . . . . . . . . . . . . . . . . . . . . . . 13 | |||
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 | 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 | |||
7.1. P2MP-TE Tree Re-evaluation Request Flag . . . . . . . . . 13 | 7.1. P2MP-TE Tree Re-evaluation Request Flag . . . . . . . . . 13 | |||
7.2. Preferable P2MP-TE Tree Exists Path Error Sub-code . . . . 13 | 7.2. Preferable P2MP-TE Tree Exists Path Error Sub-code . . . . 14 | |||
7.3. Fragment Identifier For S2L sub-LSP Descriptor . . . . . . 14 | 7.3. Fragment Identifier For S2L sub-LSP Descriptor . . . . . . 14 | |||
8. Security Considerations . . . . . . . . . . . . . . . . . . . 14 | 8. Security Considerations . . . . . . . . . . . . . . . . . . . 14 | |||
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16 | 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16 | |||
9.1. Normative References . . . . . . . . . . . . . . . . . . . 16 | 9.1. Normative References . . . . . . . . . . . . . . . . . . . 16 | |||
9.2. Informative References . . . . . . . . . . . . . . . . . . 16 | 9.2. Informative References . . . . . . . . . . . . . . . . . . 16 | |||
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 17 | Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 17 | |||
Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17 | Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17 | |||
1. Introduction | 1. Introduction | |||
skipping to change at page 4, line 27 ¶ | skipping to change at page 4, line 27 ¶ | |||
node along the path to the egress node at the time of its signaling | node along the path to the egress node at the time of its signaling | |||
by the ingress node. Such an S2L sub-LSP is signaled with no | by the ingress node. Such an S2L sub-LSP is signaled with no | |||
Explicit Route Object (ERO) [RFC3209], or with an ERO that contains | Explicit Route Object (ERO) [RFC3209], or with an ERO that contains | |||
at least one loose next-hop, or with an ERO that contains an abstract | at least one loose next-hop, or with an ERO that contains an abstract | |||
node which identifies more than one node. This is often the case | node which identifies more than one node. This is often the case | |||
with inter-domain P2MP-TE LSPs where Path Computation Element (PCE) | with inter-domain P2MP-TE LSPs where Path Computation Element (PCE) | |||
is not used [RFC5440]. | is not used [RFC5440]. | |||
As per [RFC4875], an ingress node may re-optimize the entire P2MP-TE | As per [RFC4875], an ingress node may re-optimize the entire P2MP-TE | |||
LSP tree by re-signaling all its S2L sub-LSP(s) using the | LSP tree by re-signaling all its S2L sub-LSP(s) using the | |||
Make-Before-Break (MBB) method or may re-optimize individual or a set | Make-Before-Break (MBB) method or may re-optimize individual S2L sub- | |||
of S2L sub-LSP(s) i.e. individual or a set of destination(s) using | LSP or a set of S2L sub-LSPs i.e. individual destination or a set of | |||
the Sub-Group-Based re-optimization method. | destinations, both using the Sub-Group-Based Re-optimization method. | |||
[RFC4736] defines RSVP signaling mechanisms for re-optimizing loosely | [RFC4736] defines RSVP signaling procedure for re-optimizing the | |||
routed Point-to-Point (P2P) TE LSP(s). This document discusses the | path(s) of loosely routed Point-to-Point (P2P) TE LSP(s). Those | |||
mechanisms include a method for the ingress node to trigger a new | ||||
path re-evaluation request and a method for the mid-point node to | ||||
notify availability of a preferred path. This document discusses the | ||||
application of those mechanisms to the re-optimization of loosely | application of those mechanisms to the re-optimization of loosely | |||
routed P2MP-TE LSPs, identifies issues in doing so and proposes | routed P2MP-TE LSPs, identifies issues in doing so and defines | |||
procedures to address them. | procedures to address them. | |||
For re-optimizing a group of S2L sub-LSPs in a tree using the Sub- | ||||
Group-Based Re-optimization method, an S2L sub-LSP descriptor list | ||||
can be used to signal one or more S2L sub-LSPs in an RSVP message. | ||||
This RSVP message may need to be semantically fragmented when large | ||||
number of S2L sub-LSPs are added to the descriptor list. This | ||||
document defines the notion of a fragment identifier to help | ||||
recipient nodes unambiguously reconstruct the fragmented S2L sub-LSP | ||||
descriptor list. | ||||
2. Conventions Used in This Document | 2. Conventions Used in This Document | |||
2.1. Key Word Definitions | 2.1. Key Word Definitions | |||
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 [RFC2119]. | document are to be interpreted as described in [RFC2119]. | |||
2.2. Abbreviations | 2.2. Abbreviations | |||
ABR: Area Border Router. | ABR: Area Border Router. | |||
AS: Autonomous System. | AS: Autonomous System. | |||
skipping to change at page 7, line 39 ¶ | skipping to change at page 7, line 50 ¶ | |||
In order to address above mentioned issues and to align | In order to address above mentioned issues and to align | |||
re-optimization of P2MP-TE LSP with P2P LSP [RFC4736], there is a | re-optimization of P2MP-TE LSP with P2P LSP [RFC4736], there is a | |||
need for a mechanism to trigger re-optimization of the LSP tree by | need for a mechanism to trigger re-optimization of the LSP tree by | |||
re-signaling all S2L sub-LSPs with a different LSP-ID. To meet this | re-signaling all S2L sub-LSPs with a different LSP-ID. To meet this | |||
requirement, this document defines RSVP-TE signaling extensions for | requirement, this document defines RSVP-TE signaling extensions for | |||
the ingress node to trigger the re-evaluation of the P2MP LSP tree on | the ingress node to trigger the re-evaluation of the P2MP LSP tree on | |||
every hop that has a next-hop defined as a loose or abstract hop for | every hop that has a next-hop defined as a loose or abstract hop for | |||
one or more S2L sub-LSP path, and a mid-point LSR to signal to the | one or more S2L sub-LSP path, and a mid-point LSR to signal to the | |||
ingress node that a preferable LSP tree exists (compared to the | ingress node that a preferable LSP tree exists (compared to the | |||
current path) or that the whole P2MP-TE LSP must be re-optimized | current path) or that the whole P2MP-TE LSP must be re-optimized | |||
(because of maintenance required on the TE LSP path). | (because of maintenance required on the TE LSP path) (see Section | |||
4.1). | ||||
3.3. Existing Mechanism For Sub-Group-Based P2MP-TE LSP Re-optimization | 3.3. Existing Mechanism For Sub-Group-Based P2MP-TE LSP Re-optimization | |||
Applying the procedures discussed in RFC4736 in conjunction with the | Applying the procedures discussed in RFC4736 in conjunction with the | |||
Sub-Group-Based Re-Optimization procedures ([RFC4875], Section 14.2), | Sub-Group-Based Re-Optimization procedures ([RFC4875], Section 14.2), | |||
an ingress node MAY trigger path re-evaluation requests for a set of | an ingress node MAY trigger path re-evaluation requests for a set of | |||
S2L sub-LSPs in a single Path message using S2L sub-LSP descriptor | S2L sub-LSPs in a single Path message using S2L sub-LSP descriptor | |||
list. Similarly, a mid-point LSR may send a PathErr with the Notify | list. Similarly, a mid-point LSR may send a PathErr with the Notify | |||
error code 25 and sub-code 6 containing a list of S2L sub-LSPs | error code 25 and sub-code 6 containing a list of S2L sub-LSPs | |||
transiting through the LSR using an S2L sub-LSP descriptor list to | transiting through the LSR using an S2L sub-LSP descriptor list to | |||
skipping to change at page 8, line 34 ¶ | skipping to change at page 8, line 47 ¶ | |||
sub-sets of S2L sub-LSPs in each (due to either the combined Path | sub-sets of S2L sub-LSPs in each (due to either the combined Path | |||
message getting fragmented or the combined PathErr message getting | message getting fragmented or the combined PathErr message getting | |||
fragmented) and would require additional logic to determine how to | fragmented) and would require additional logic to determine how to | |||
re-optimize the LSP tree (for example, waiting for some time to | re-optimize the LSP tree (for example, waiting for some time to | |||
aggregate all possible PathErr messages before taking an action). | aggregate all possible PathErr messages before taking an action). | |||
When fragmented, RSVP messages may arrive out of order, and the | When fragmented, RSVP messages may arrive out of order, and the | |||
receiver has no way of knowing the beginning and end of the S2L | receiver has no way of knowing the beginning and end of the S2L | |||
sub-LSP list. | sub-LSP list. | |||
In order to address the above mentioned issues caused by RSVP message | In order to address the above mentioned issues caused by RSVP message | |||
semantic fragmentation, this document proposes the use of fragment | semantic fragmentation, this document defines new fragment identifier | |||
identifier for the S2L sub-LSP descriptor list when combining large | object for the S2L sub-LSP descriptor list when combining large | |||
number of S2L sub-LSPs in an RSVP message. | number of S2L sub-LSPs in an RSVP message (see Section 4.2). | |||
4. Signaling Procedure For Loosely Routed P2MP-TE LSP Re-optimization | 4. Signaling Extensions For Loosely Routed P2MP-TE LSP Re-optimization | |||
4.1. Tree-Based Re-optimization | 4.1. Tree-Based Re-optimization | |||
To evaluate a P2MP-TE LSP tree on mid-point LSRs that expand loose | To evaluate a P2MP-TE LSP tree on mid-point LSRs that expand loose | |||
next-hop(s), an ingress node MAY send a Path message with "P2MP-TE | next-hop(s), an ingress node MAY send a Path message with "P2MP-TE | |||
Tree Re-evaluation Request (value TBA1)" defined in this document. | Tree Re-evaluation Request (value TBA1)" defined in this document. | |||
The ingress node selects one of the S2L sub-LSPs of the P2MP-TE LSP | The ingress node selects one of the S2L sub-LSPs of the P2MP-TE LSP | |||
tree transiting a mid-point LSR to trigger the re-evaluation request. | tree transiting a mid-point LSR to trigger the re-evaluation request. | |||
The ingress node MAY send a re-evaluation request to each border LSR | The ingress node MAY send a re-evaluation request to each border LSR | |||
on the path of the LSP tree. | on the path of the LSP tree. | |||
A mid-point LSR that expands loose next-hop(s) for one or more S2L | A mid-point LSR that expands loose next-hop(s) for one or more S2L | |||
sub-LSP path(s) SHOULD do the following upon receiving a Path message | sub-LSP path(s) does the following upon receiving a Path message with | |||
with the "P2MP-TE Tree Re-evaluation Request" flag set: | the "P2MP-TE Tree Re-evaluation Request" flag set: | |||
o The mid-point LSR SHOULD check for a preferable P2MP-TE LSP tree | o The mid-point LSR MUST check for a preferable P2MP-TE LSP tree by | |||
by re-evaluating all S2L sub-LSP(s) that are expanded paths of the | re-evaluating all S2L sub-LSP(s) that are expanded paths of the | |||
loose next-hops of the P2MP-TE LSP. | loose next-hops of the P2MP-TE LSP. | |||
o If a preferable P2MP-TE LSP tree is found, the mid-point LSR MAY | o If a preferable P2MP-TE LSP tree is found, the mid-point LSR MUST | |||
send an RSVP PathErr with the Notify error code 25 defined in | send an RSVP PathErr with the Notify error code 25 defined in | |||
[RFC3209] and sub-code "Preferable P2MP-TE Tree Exists (value | [RFC3209] and sub-code "Preferable P2MP-TE Tree Exists (value | |||
TBA2)" defined in this document to the ingress node. The mid- | TBA2)" defined in this document to the ingress node. The mid- | |||
point LSR, in turn, SHOULD NOT propagate the "P2MP-TE Tree Re- | point LSR, in turn, SHOULD NOT propagate the "P2MP-TE Tree Re- | |||
evaluation Request" flag in the subsequent RSVP Path messages sent | evaluation Request" flag in the subsequent RSVP Path messages sent | |||
downstream for the re-evaluated P2MP-TE LSP. | downstream for the re-evaluated P2MP-TE LSP. | |||
o If no preferable tree for P2MP-TE LSP can be found, the | o If no preferable tree for P2MP-TE LSP can be found, the mid-point | |||
recommended mode is that the mid-point LSR that expands loose | LSR that expands loose next-hop(s) for one or more S2L sub-LSP | |||
next-hop(s) for one or more S2L sub-LSP path(s) SHOULD propagate | path(s) MUST propagate the request downstream by setting the | |||
the request downstream by setting the "P2MP-TE Tree Re-evaluation | "P2MP-TE Tree Re-evaluation Request" flag in the LSP_ATTRIBUTES | |||
Request" flag in the LSP_ATTRIBUTES Object of the RSVP Path | Object of the RSVP Path message. | |||
message. | ||||
A mid-point LSR MAY send an unsolicited PathErr with the Notify error | A mid-point LSR MAY send an unsolicited PathErr with the Notify error | |||
code and sub-code "Preferable P2MP-TE Tree Exists" to the ingress | code and sub-code "Preferable P2MP-TE Tree Exists" to the ingress | |||
node to notify of a preferred P2MP-TE LSP tree when it determines it | node to notify of a preferred P2MP-TE LSP tree when it determines it | |||
exists. In this case, the mid-point LSR that expands loose next- | exists. In this case, the mid-point LSR that expands loose next- | |||
hop(s) for one or more S2L sub-LSP path(s) selects one of the S2L | hop(s) for one or more S2L sub-LSP path(s) selects one of the S2L | |||
sub-LSP(s) of the P2MP-TE LSP tree to send this PathErr message to | sub-LSP(s) of the P2MP-TE LSP tree to send this PathErr message to | |||
the ingress node. | the ingress node. | |||
The sending of an RSVP PathErr with the Notify error code and | The sending of an RSVP PathErr with the Notify error code and | |||
"Preferable P2MP-TE Tree Exists" sub-code to the ingress node | "Preferable P2MP-TE Tree Exists" sub-code to the ingress node | |||
notifies the ingress node of the existence of a preferable P2MP-TE | notifies the ingress node of the existence of a preferable P2MP-TE | |||
LSP tree and upon receiving this PathErr, the ingress node MAY | LSP tree and upon receiving this PathErr, the ingress node MUST | |||
trigger re-optimization of the LSP using the MBB method with a | trigger re-optimization of the LSP using the MBB method with a | |||
different LSP-ID. | different LSP-ID. | |||
4.2. Sub-Group-Based Re-optimization Using Fragment Identifier | 4.2. Sub-Group-Based Re-optimization Using Fragment Identifier | |||
It might be preferable, as per [RFC4875], to re-optimize the entire | It might be preferable, as per [RFC4875], to re-optimize the entire | |||
P2MP-TE LSP by re-signaling all of its S2L sub-LSP(s) (Section 14.1, | P2MP-TE LSP by re-signaling all of its S2L sub-LSP(s) (Section 14.1, | |||
"Make-before-Break") or to re-optimize individual or group of S2L | "Make-before-Break") or to re-optimize individual or group of S2L | |||
sub-LSP(s) i.e. individual or group of destination(s) (Section 14.2 | sub-LSP(s) i.e. individual or group of destination(s) (Section 14.2 | |||
"Sub-Group-Based Re-Optimization" in [RFC4875]), both using the same | "Sub-Group-Based Re-Optimization" in [RFC4875]), both using the same | |||
skipping to change at page 14, line 44 ¶ | skipping to change at page 15, line 6 ¶ | |||
8. Security Considerations | 8. Security Considerations | |||
This document defines RSVP-TE signaling extensions to allow an | This document defines RSVP-TE signaling extensions to allow an | |||
ingress node of a P2MP-TE LSP to request the re-evaluation of the LSP | ingress node of a P2MP-TE LSP to request the re-evaluation of the LSP | |||
tree downstream of a node, and for a mid-point LSR to notify the | tree downstream of a node, and for a mid-point LSR to notify the | |||
ingress node of the existence of a preferable tree by sending a | ingress node of the existence of a preferable tree by sending a | |||
PathErr. As per [RFC4736], in the case of a P2MP-TE LSP S2L sub-LSP | PathErr. As per [RFC4736], in the case of a P2MP-TE LSP S2L sub-LSP | |||
spanning multiple domains, it may be desirable for a mid-point LSR to | spanning multiple domains, it may be desirable for a mid-point LSR to | |||
modify the RSVP PathErr message defined in this document to preserve | modify the RSVP PathErr message defined in this document to preserve | |||
confidentiality across domains. Furthermore, an ingress node may | confidentiality across domains. | |||
decide to ignore this PathErr message coming from a mid-point LSR | ||||
residing in another domain. Similarly, a mid-point LSR may decide to | ||||
ignore the P2MP-TE tree re-evaluation request originating from | ||||
another ingress domain. | ||||
This document also defines fragment identifier for the S2L sub-LSP | This document also defines fragment identifier for the S2L sub-LSP | |||
descriptor when combining large number of S2L sub-LSPs in an RSVP | descriptor when combining large number of S2L sub-LSPs in an RSVP | |||
message and the message needs to be semantically fragmented. The | message and the message needs to be semantically fragmented. The | |||
introduction of the fragment identifier, by itself, introduces no | introduction of the fragment identifier, by itself, introduces no | |||
additional information to signaling. For a general discussions on | additional information to signaling. For a general discussion on | |||
MPLS and GMPLS related security issues, see the MPLS/GMPLS security | MPLS and GMPLS related security issues, see the MPLS/GMPLS security | |||
framework [RFC5920]. | framework [RFC5920]. | |||
9. References | 9. References | |||
9.1. Normative References | 9.1. Normative References | |||
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate | [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate | |||
Requirement Levels", BCP 14, RFC 2119, March 1997. | Requirement Levels", BCP 14, RFC 2119, March 1997. | |||
skipping to change at page 17, line 8 ¶ | skipping to change at page 17, line 8 ¶ | |||
[RFC5920] Fang, L., "Security Framework for MPLS and GMPLS | [RFC5920] Fang, L., "Security Framework for MPLS and GMPLS | |||
Networks", RFC 5920, July 2010. | Networks", RFC 5920, July 2010. | |||
[RFC6510] Berger, L. and G. Swallow, "Resource Reservation Protocol | [RFC6510] Berger, L. and G. Swallow, "Resource Reservation Protocol | |||
(RSVP) Message Formats for Label Switched Path (LSP) | (RSVP) Message Formats for Label Switched Path (LSP) | |||
Attributes Objects", RFC 6510, February 2012. | Attributes Objects", RFC 6510, February 2012. | |||
Acknowledgments | Acknowledgments | |||
The authors would like to thank Loa Andersson, Sriganesh Kini, Curtis | The authors would like to thank Loa Andersson, Sriganesh Kini, Curtis | |||
Villamizar, Dimitri Papadimitriou, Nobo Akiya and Vishnu Pavan Beeram | Villamizar, Dimitri Papadimitriou, Nobo Akiya, Vishnu Pavan Beeram | |||
for reviewing this document and providing many useful comments and | and Joel M. Halpern for reviewing this document and providing many | |||
suggestions. The authors would also like to thank Ling Zeng with | useful comments and suggestions. The authors would also like to | |||
Cisco Systems for implementing mechanisms defined in this document. | thank Ling Zeng with Cisco Systems for implementing mechanisms | |||
A special thanks to Adrian Farrel for his thorough review of this | defined in this document. A special thanks to Adrian Farrel for his | |||
document. | thorough review of this document. | |||
Author's Addresses | Author's Addresses | |||
Tarek Saad (editor) | Tarek Saad (editor) | |||
Cisco Systems | Cisco Systems | |||
EMail: tsaad@cisco.com | EMail: tsaad@cisco.com | |||
Rakesh Gandhi (editor) | Rakesh Gandhi (editor) | |||
Cisco Systems | Cisco Systems | |||
End of changes. 27 change blocks. | ||||
68 lines changed or deleted | 64 lines changed or added | |||
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