--- 1/draft-ietf-mpls-git-uus-03.txt 2006-02-05 00:39:22.000000000 +0100 +++ 2/draft-ietf-mpls-git-uus-04.txt 2006-02-05 00:39:22.000000000 +0100 @@ -1,18 +1,18 @@ Network Working Group Muneyoshi Suzuki INTERNET DRAFT NTT -Expires January 26, 2000 July 26, 1999 +Expires July 11, 2000 January 11, 2000 The Assignment of the Information Field and Protocol Identifier in the Q.2941 Generic Identifier and Q.2957 User-to-user Signaling for the Internet Protocol - + Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. @@ -147,23 +147,23 @@ information elements are all capable of transferring this information. Considering the original purposes of these information elements, the most appropriate one to use is the Generic Identifier information element. 2.2 QoS-sensitive Session Signaling The major difference between QoS-sensitive session signaling and long-lived session signaling is that call setup is not initiated by the detection of a long-lived session, but is explicitly initiated by - the setup protocol such as ST2+ and RSVP. To implement QoS-sensitive - session signaling using ATM, the ATM network between the routers must - forward not only the session identifier but also the setup protocol. + the setup protocol such as RSVP. To implement QoS-sensitive session + signaling using ATM, the ATM network between the routers must forward + not only the session identifier but also the setup protocol. There are two schemes for forwarding the setup protocol. One is to multiplex the protocol into a default VC connecting the routers, or to forward the protocol through a particular VC. In this case, the QoS-sensitive session and the ATM VC are established sequentially. The second scheme is to forward the setup protocol as an information element in the B-ISDN signaling. In this case, the QoS-sensitive session and the ATM VC are established simultaneously. The latter scheme has the following advantages compared with the former one. @@ -211,25 +211,25 @@ | |<------------| | | | | |------------>| | | | |<-| CONN ACK | | | | <----------| | | | | | N-CONNECT | | -ACK Fig. 2.2: Example procedure for simultaneous QoS-sensitive session and ATM VC establishment. - Both ST2+ and RSVP are currently proposed for the setup protocol and - new setup protocols are likely to be developed in the near future. - Therefore, to generalize the discussion, the procedure for the setup - protocol in this example is the general connection setup procedure - using confirmed service. + RSVP is currently proposed for the setup protocol and new setup + protocols are likely to be developed in the future. Therefore, to + generalize the discussion, the procedure for the setup protocol in + this example is the general connection setup procedure using + confirmed service. To implement this signaling procedure, the B-ISDN signaling must include the User-user information element that the capacity is sufficient to forward the setup protocol. 3. Overview of the Generic Identifier and User-to-user Signaling 3.1 Overview of the Generic Identifier The Generic Identifier enables the transfer of identifiers between @@ -328,27 +328,27 @@ The SETUP, ALERTING, CONNECT, RELEASE, RELEASE COMPLETE, PROGRESS, ADD PARTY, PARTY ALERTING, ADD PARTY ACK, ADD PARTY REJECT, DROP PARTY, and DROP PARTY ACK messages that are transferred between end- to-end users in the ATM network may contain a User-user information element. The ATM network transfers the User-user information element transparently if it contains no coding rule errors. From the viewpoint of B-ISDN signaling applications, it seems the Generic Identifier and User-to-user Signaling are similar functions. But their rules for processing exceptions are not completely the - same, because their purposes are different. The Generic Identifier is - designed for the transfer of identifiers between the c-planes, while - the User-to-user Signaling is designed for the transfer of user data - via the c-planes. Another difference is that the latter supports - interworking with the user-user information element in the Q.931 N- - ISDN signaling, but the Generic Identifier does not. Note that the - ATM network may check the contents of the Generic Identifier + same, because their purposes are different. The Generic Identifier + is designed for the transfer of identifiers between the c-planes, + while the User-to-user Signaling is designed for the transfer of user + data via the c-planes. Another difference is that the latter + supports interworking with the user-user information element in the + Q.931 N-ISDN signaling, but the Generic Identifier does not. Note + that the ATM network may check the contents of the Generic Identifier information element, but does not check the contents of the User-to- user information element. The format of the User-user information element is shown in Fig. 3.2. Bits 8 7 6 5 4 3 2 1 Octets +-----+-----+-----+-----+-----+-----+-----+-----+ | Information element identifier | | = User-user information element (0x7E) | 1 @@ -436,22 +436,20 @@ The Identifier value field is assigned to Internet protocol related information which is identified by the Identifier related standard/application field and Identifier type field. The following identifiers are specified. Std./app. Id type IPv4 session identifier IPv4 Session - ST2+ session identifier ST2+ Session - IPv6 session identifier IPv6 Session MPLS VCID MPLS Resource Exp./Org. specific IPv4/ST2+/IPv6/MPLS Experiment As described in section 3.1, the B-ISDN signaling message transferred between end-to-end users may contain up to three Generic Identifier information elements. These elements may contain multiple identifiers. This document does not specify the order of identifiers @@ -516,55 +513,27 @@ The Identifier length is 13 octets. The Source IPv4 address, Destination IPv4 address, Protocol, Source Port, and Destination Port [7, 9, 10] are assigned in that order to the Identifier value field. Note: This specific session identifier is intended for use only with the explicit reservation. If wild card associations are needed at a later date, another identifier type will be used. -4.1.3 ST2+ session identifier - - If the Identifier related standard/application field in the Generic - Identifier information element is the ST2+, and the Identifier type - field in the identifier is the Session, the identifier is the ST2+ - session identifier. The format of the ST2+ session identifier is - shown in Fig. 4.3. - - Bits Octet - 8 7 6 5 4 3 2 1 length - +-----+-----+-----+-----+-----+-----+-----+-----+ - | Identifier type | - | = Session (0x01) | 1 - +-----+-----+-----+-----+-----+-----+-----+-----+ - | Identifier length | - | = 6 octets (0x06) | 1 - +-----+-----+-----+-----+-----+-----+-----+-----+ - | Stream ID (SID) | 6 - +-----+-----+-----+-----+-----+-----+-----+-----+ - - Fig. 4.3: ST2+ session identifier. - - The Identifier type field is the Session (0x01). - - The Identifier length is 6 octets. - - The Stream ID (SID) [11] is assigned to the Identifier value field. - -4.1.4 IPv6 session identifier +4.1.3 IPv6 session identifier If the Identifier related standard/application field in the Generic Identifier information element is the IPv6, and the Identifier type field in the identifier is the Session, the identifier is the IPv6 session identifier. The format of the IPv6 session identifier is - shown in Fig. 4.4. + shown in Fig. 4.3. Bits Octet 8 7 6 5 4 3 2 1 length +-----+-----+-----+-----+-----+-----+-----+-----+ | Identifier type | | = Session (0x01) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | Identifier length | | = 37 octets (0x25) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ @@ -572,101 +541,101 @@ +-----+-----+-----+-----+-----+-----+-----+-----+ | Destination IPv6 address | 16 +-----+-----+-----+-----+-----+-----+-----+-----+ | Protocol | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | Source Port | 2 +-----+-----+-----+-----+-----+-----+-----+-----+ | Destination Port | 2 +-----+-----+-----+-----+-----+-----+-----+-----+ - Fig. 4.4: IPv6 session identifier. + Fig. 4.3: IPv6 session identifier. The Identifier type field is the Session (0x01). The Identifier length is 37 octets. The Source IPv6 address, Destination IPv6 address, Protocol, Source Port, and Destination Port [8, 9, 10] are assigned in that order to the Identifier value field. Note: This specific session identifier is intended for use only with the explicit reservation. If wild card associations are needed at a later date, another identifier type will be used. -4.1.5 MPLS VCID +4.1.4 MPLS VCID If the Identifier related standard/application field in the Generic Identifier information element is the MPLS, and the Identifier type field in the identifier is the Resource, the identifier is the MPLS - VCID. The format of the MPLS VCID is shown in Fig. 4.5. + VCID. The format of the MPLS VCID is shown in Fig. 4.4. Bits Octet 8 7 6 5 4 3 2 1 length +-----+-----+-----+-----+-----+-----+-----+-----+ | Identifier type | | = Resource (0x02) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | Identifier length | | = 4 octets (0x04) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | MPLS VCID | 4 +-----+-----+-----+-----+-----+-----+-----+-----+ - Fig. 4.5: MPLS VCID. + Fig. 4.4: MPLS VCID. The Identifier type field is the Resource (0x02). The Identifier length is 4 octets. The MPLS VCID [13] is assigned to the Identifier value field. -4.1.6 Experiment/Organization specific +4.1.5 Experiment/Organization specific If the Identifier related standard/application field in the Generic Identifier information element is the IPv4, ST2+, IPv6, or MPLS, and the Identifier type field in the identifier is the Experiment/Organization specific, the identifier is the Experiment/Organization specific. The format of the - Experiment/Organization specific is shown in Fig. 4.6. + Experiment/Organization specific is shown in Fig. 4.5. Bits Octet 8 7 6 5 4 3 2 1 length +-----+-----+-----+-----+-----+-----+-----+-----+ | Identifier type | | = Experiment/Organization specific (0xFE) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | Identifier length | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | Organizationally unique identifier (OUI) | 3 +-----+-----+-----+-----+-----+-----+-----+-----+ | Experiment/Organization specific info. | = = | | +-----+-----+-----+-----+-----+-----+-----+-----+ - Fig. 4.6: Experiment/Organization specific. + Fig. 4.5: Experiment/Organization specific. The Identifier type field is the Experiment/Organization specific (0xFE). The first 3 octets in the Identifier value field must contain the - Organizationally unique identifier (OUI) (as specified in IEEE 802- - 1990; section 5.1). + Organizationally unique identifier (OUI) (as specified in IEEE + 802-1990; section 5.1). 4.2 Assignment in the User-user Information Element 4.2.1 Use of User-to-user Signaling The information field and protocol identifier assignment principle for the Internet protocol in the User-user information element is - shown in Fig. 4.7. + shown in Fig. 4.6. Bits 8 7 6 5 4 3 2 1 Octets +-----+-----+-----+-----+-----+-----+-----+-----+ | Information element identifier | | = User-user information element (0x7E) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | 1 | Coding | IE instruction field | | Ext | standard |Flag |Res. | IE action ind. | 2 +-----+-----+-----+-----+-----+-----+-----+-----+ @@ -675,32 +644,32 @@ | Protocol discriminator | | = Internet protocol/application (0x06) | 5 +-----+-----+-----+-----+-----+-----+-----+-----+ | Internet protocol/application identifier | 6 +-----+-----+-----+-----+-----+-----+-----+-----+ | Internet protocol/application related info. | 7- = = | | +-----+-----+-----+-----+-----+-----+-----+-----+ - Fig. 4.7: Principle of assignment in the User-user information element. + Fig. 4.6: Principle of assignment in the User-user information element. The Protocol discriminator field is the Internet protocol/application (0x06). In this case, the first 1 octet in the User information field is the Internet protocol/application identifier field. Assignment of the Internet protocol/application identifier field is as follows. A leading 0x means hexadecimal. 0x00: Reserved. - 0x01: ST2+ SCMP. + 0x01: Reserved for ST2+. 0x02: RSVP message. 0x03-0xFD: Reserved for IANA assignment. 0xFE: Experiment/Organization specific. 0xFF: Reserved. The field that follows the Internet protocol/application identifier @@ -718,62 +687,23 @@ To enable reliable User-user information element transfer, when the calling party sends a SETUP or ADD PARTY message with a User-user information element, the CONNECT or ADD PARTY ACK message returned by the called party must contain a User-user information element. The called party may not respond with the same user information received from the calling party. The calling party should confirm that the response message contains a User-user information element. This rule enables negotiation; this document does not specify the detailed procedure of this negotiation. -4.2.2 ST2+ SCMP - - The format of the ST2+ SCMP is shown in Fig. 4.8. - - Bits - 8 7 6 5 4 3 2 1 Octets - +-----+-----+-----+-----+-----+-----+-----+-----+ - | Information element identifier | - | = User-user information element (0x7E) | 1 - +-----+-----+-----+-----+-----+-----+-----+-----+ - | 1 | Coding | IE instruction field | - | Ext | standard |Flag |Res. | IE action ind. | 2 - +-----+-----+-----+-----+-----+-----+-----+-----+ - | Length of contents of information element | 3-4 - +-----+-----+-----+-----+-----+-----+-----+-----+ - | Protocol discriminator | - | = Internet protocol/application (0x06) | 5 - +-----+-----+-----+-----+-----+-----+-----+-----+ - | Internet protocol/application identifier | - | = ST2+ SCMP (0x01) | 6 - +-----+-----+-----+-----+-----+-----+-----+-----+ - | ST2+ SCMP | 7- - = = - | | - +-----+-----+-----+-----+-----+-----+-----+-----+ - - Fig. 4.8: ST2+ SCMP. - - The Internet protocol/application identifier field is the ST2+ SCMP - (0x01). - - The ST2+ SCMP [11] is assigned to the Internet protocol/application - related information field. The SETUP and ADD PARTY messages may - contain the ST2+ SCMP CONNECT message. The CONNECT and ADD PARTY ACK - messages may contain the ST2+ SCMP ACCEPT message. The RELEASE and - DROP PARTY messages may contain the ST2+ SCMP DISCONNECT message. - The RELEASE, RELEASE COMPLETE, ADD PARTY REJECT, and DROP PARTY - messages may contain the ST2+ SCMP REFUSE message. - -4.2.3 RSVP message +4.2.2 RSVP message - The format of the RSVP message is shown in Fig. 4.9. + The format of the RSVP message is shown in Fig. 4.7. Bits 8 7 6 5 4 3 2 1 Octets +-----+-----+-----+-----+-----+-----+-----+-----+ | Information element identifier | | = User-user information element (0x7E) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | 1 | Coding | IE instruction field | | Ext | standard |Flag |Res. | IE action ind. | 2 +-----+-----+-----+-----+-----+-----+-----+-----+ @@ -783,35 +713,35 @@ | = Internet protocol/application (0x06) | 5 +-----+-----+-----+-----+-----+-----+-----+-----+ | Internet protocol/application identifier | | = RSVP message (0x02) | 6 +-----+-----+-----+-----+-----+-----+-----+-----+ | RSVP message | 7- = = | | +-----+-----+-----+-----+-----+-----+-----+-----+ - Fig. 4.9: RSVP message. + Fig. 4.7: RSVP message. The Internet protocol/application identifier field is the RSVP message (0x02). The RSVP message [12] is assigned to the Internet protocol/application related information field. The SETUP message may contain the RSVP Resv message. The CONNECT message may contain the RSVP ResvConf message. The RELEASE message may contain the RSVP ResvErr or ResvTear message. -4.2.4 Experiment/Organization specific +4.2.3 Experiment/Organization specific The format of the Experiment/Organization specific is shown in Fig. - 4.10. + 4.8. Bits 8 7 6 5 4 3 2 1 Octets +-----+-----+-----+-----+-----+-----+-----+-----+ | Information element identifier | | = User-user information element (0x7E) | 1 +-----+-----+-----+-----+-----+-----+-----+-----+ | 1 | Coding | IE instruction field | | Ext | standard |Flag |Res. | IE action ind. | 2 +-----+-----+-----+-----+-----+-----+-----+-----+ @@ -823,21 +753,21 @@ | Internet protocol/application identifier | | = Experiment/Organization specific (0xFE) | 6 +-----+-----+-----+-----+-----+-----+-----+-----+ | Organizationally unique identifier (OUI) | 7-9 +-----+-----+-----+-----+-----+-----+-----+-----+ | Experiment/Organization specific info. | 10- = = | | +-----+-----+-----+-----+-----+-----+-----+-----+ - Fig. 4.10: Experiment/Organization specific. + Fig. 4.8: Experiment/Organization specific. The Internet protocol/application identifier field is the Experiment/Organization specific (0xFE). The first 3 octets in the Internet protocol/application related information field must contain the Organizationally unique identifier (OUI) (as specified in IEEE 802-1990; section 5.1). 5. Open Issues @@ -878,20 +808,94 @@ assignment in the Q.2941 Generic Identifier and Q.2957 User-to-user Signaling for the Internet protocol, so these do not weaken the security of the B-ISDN signaling. In a called party of the B-ISDN signaling, if the incoming SETUP message contains the calling party number and if it is verified and passed by the ATM network or it is provided by the network, then it is feasible to use the calling party number for part of the calling party authentication to strengthen security. +Appendix. Information Field and Protocol Identifier Assignment for ST2+ + + This appendix specifies information field and protocol identifier + assignment in the Generic Identifier and User-to-user Signaling for + ST2+. Note that this appendix is NOT part of the standard. + +A.1 ST2+ session identifier + + If the Identifier related standard/application field in the Generic + Identifier information element is the ST2+, and the Identifier type + field in the identifier is the Session, the identifier is the ST2+ + session identifier. The format of the ST2+ session identifier is + shown in Fig. A.1. + + Bits Octet + 8 7 6 5 4 3 2 1 length + +-----+-----+-----+-----+-----+-----+-----+-----+ + | Identifier type | + | = Session (0x01) | 1 + +-----+-----+-----+-----+-----+-----+-----+-----+ + | Identifier length | + | = 6 octets (0x06) | 1 + +-----+-----+-----+-----+-----+-----+-----+-----+ + | Stream ID (SID) | 6 + +-----+-----+-----+-----+-----+-----+-----+-----+ + + Fig. A.1: ST2+ session identifier. + + The Identifier type field is the Session (0x01). + + The Identifier length is 6 octets. + + The Stream ID (SID) [11] is assigned to the Identifier value field. + +A.2 ST2+ SCMP + + The format of the User-user information element for the ST2+ SCMP is + shown in Fig. A.2. + + Bits + 8 7 6 5 4 3 2 1 Octets + +-----+-----+-----+-----+-----+-----+-----+-----+ + | Information element identifier | + | = User-user information element (0x7E) | 1 + +-----+-----+-----+-----+-----+-----+-----+-----+ + | 1 | Coding | IE instruction field | + | Ext | standard |Flag |Res. | IE action ind. | 2 + +-----+-----+-----+-----+-----+-----+-----+-----+ + | Length of contents of information element | 3-4 + +-----+-----+-----+-----+-----+-----+-----+-----+ + | Protocol discriminator | + | = Internet protocol/application (0x06) | 5 + +-----+-----+-----+-----+-----+-----+-----+-----+ + | Internet protocol/application identifier | + | = ST2+ SCMP (0x01) | 6 + +-----+-----+-----+-----+-----+-----+-----+-----+ + | ST2+ SCMP | 7- + = = + | | + +-----+-----+-----+-----+-----+-----+-----+-----+ + + Fig. A.2: ST2+ SCMP. + + The Internet protocol/application identifier field is the ST2+ SCMP + (0x01). + + The ST2+ SCMP [11] is assigned to the Internet protocol/application + related information field. The SETUP and ADD PARTY messages may + contain the ST2+ SCMP CONNECT message. The CONNECT and ADD PARTY ACK + messages may contain the ST2+ SCMP ACCEPT message. The RELEASE and + DROP PARTY messages may contain the ST2+ SCMP DISCONNECT message. + The RELEASE, RELEASE COMPLETE, ADD PARTY REJECT, and DROP PARTY + messages may contain the ST2+ SCMP REFUSE message. + References [1] ITU-T, "Broadband Integrated Services Digital Network (B- ISDN)-Digital Subscriber Signaling System No. 2 (DSS 2)-User- Network Interface (UNI) Layer 3 Specification for Basic Call/Connection Control," ITU-T Recommendation Q.2931, September 1995. [2] ITU-T, "Broadband Integrated Services Digital Network (B- ISDN)-Digital Subscriber Signaling System No. 2 (DSS 2)-User- @@ -944,22 +948,22 @@ Considerations Section in RFCs," RFC 2434, October 1998. [15] P. Newman, T. Lyon, and G. Minshall, "Flow Labelled IP: A Connectionless Approach to ATM," Proc. IEEE Infocom, March 1996. [16] S. Damaskos and A. Gavras, "Connection Oriented Protocols over ATM: A case study," Proc. SPIE, Vol. 2188, pp.226-278, February 1994. [17] ITU-T, "Integrated Services Digital Network (ISDN) Overall - Network Aspects and Functions ISDN Protocol Reference Model," - ITU-T Recommendation I.320, November 1993. + Network Aspects and Functions ISDN Protocol Reference Model," ITU- + T Recommendation I.320, November 1993. [18] ITU-T, "Digital Subscriber Signaling System No. 1 (DSS 1) Specification of a Synchronization and Coordination Function for the Provision of the OSI Connection-mode Network Service in an ISDN Environment," ITU-T Recommendation Q.923, February 1995. Acknowledgments I would like to thank Kenichi Kitami of the NTT Information Sharing Lab. Group, who is also the chair of ITU-T SG11 WP1,