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diff --git a/doc/rfc/rfc3496.txt b/doc/rfc/rfc3496.txt new file mode 100644 index 0000000..781679d --- /dev/null +++ b/doc/rfc/rfc3496.txt @@ -0,0 +1,339 @@ + + + + + + +Network Working Group A. G. Malis +Request for Comments: 3496 T. Hsiao +Category: Informational Vivace Networks + March 2003 + + + Protocol Extension for Support of Asynchronous Transfer Mode (ATM) + Service Class-aware Multiprotocol Label Switching (MPLS) + Traffic Engineering + +Status of this Memo + + This memo provides information for the Internet community. It does + not specify an Internet standard of any kind. Distribution of this + memo is unlimited. + +Copyright Notice + + Copyright (C) The Internet Society (2003). All Rights Reserved. + +Abstract + + This document specifies a Resource ReSerVation Protocol-Traffic + Engineering (RSVP-TE) signaling extension for support of Asynchronous + Transfer Mode (ATM) Service Class-aware Multiprotocol Label Switching + (MPLS) Traffic Engineering. + +Table of Contents + + 1. Overview......................................................2 + 2. Extended RSVP-TE Path Message Format..........................2 + 2.1 PATH Message Format.......................................3 + 3. ATM_SERVICECLASS Object.......................................3 + 4. Handling the ATM_SERVICECLASS Object..........................4 + 5. Non-support of the ATM_SERVICECLASS Object....................4 + 6. Security Considerations.......................................4 + 7. IANA Considerations...........................................5 + 8. References....................................................5 + 9. Authors' Addresses............................................5 + 10. Full Copyright Statement......................................6 + + + + + + + + + + + +Malis & Hsiao Informational [Page 1] + +RFC 3496 ATM Service Class-aware MPLS Traffic Engineering March 2003 + + +1. Overview + + This document defines a Resource ReSerVation Protocol-Traffic + Engineering (RSVP-TE) protocol addition to support ATM (Asynchronous + Transfer Mode) Service Class-aware MPLS (MultiProtocol Label + Switching) Traffic Engineering. + + This protocol addition is used with all MPLS Label Switched Routers + (LSRs) and link types (including, but not restricted to, Packet over + SONET, Ethernet, and ATM links) to signal traffic engineered paths + that can support the ATM service classes as defined by the ATM Forum + [TM]. This document does not specify HOW to actually implement the + functionality in the MPLS LSRs to emulate the ATM Forum service + classes (such as necessary queuing and scheduling mechanisms), only + how to signal that the TE path must support the ATM Forum service + classes. A useful application for such paths is the carriage of ATM + cells encapsulated in IP or MPLS packets in order to use MPLS + networks as functional replacements for ATM networks. + +2. Extended RSVP-TE Path Message Format + + One new RSVP-TE Object is defined in this document: the + ATM_SERVICECLASS Object. Detailed description of this Object is + provided below. This new Object is applicable to PATH messages. + This specification only defines the use of the ATM_SERVICECLASS + Object in PATH messages used to establish LSP (Label Switched Path) + Tunnels in accordance with [RSVP-TE]. Such PATH messages contain a + Session Object with a C-Type equal to LSP_TUNNEL_IPv4 and a + LABEL_REQUEST object. + + Restrictions defined in [RSVP-TE] for support of establishment of LSP + Tunnels via RSVP-TE are also applicable to the establishment of LSP + Tunnels supporting ATM Service Class-aware traffic engineering. For + instance, only unicast LSPs are supported and Multicast LSPs are for + further study. + + This new ATM_SERVICECLASS object is optional with respect to RSVP-TE + so that general RSVP-TE implementations not concerned with ATM + Service Class-aware traffic engineering MPLS LSP setup do not have to + support this object. + + + + + + + + + + + +Malis & Hsiao Informational [Page 2] + +RFC 3496 ATM Service Class-aware MPLS Traffic Engineering March 2003 + + +2.1 PATH Message Format + + The format of the extended PATH message is as follows: + + <PATH Message> ::= <Common Header> [ <INTEGRITY> ] + <SESSION> <RSVP_HOP> + <TIME_VALUES> + [ <EXPLICIT_ROUTE> ] + <LABEL_REQUEST> + [ <SESSION_ATTRIBUTE> ] + [ <DIFFSERV> ] + [ <ATM_SERVICECLASS> ] + [ <POLICY_DATA> ... ] + [ <sender descriptor> ] + + <sender descriptor> ::= <SENDER_TEMPLATE> [ <SENDER_TSPEC> ] + [ <ADSPEC> ] + [ <RECORD_ROUTE> ] + +3. ATM_SERVICECLASS Object + + The ATM_SERVICECLASS object format is as follows: + + Class Number = 227, C_Type = 1 + + 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 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Reserved | SC | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + + Reserved : 29 bits + This field is reserved. It must be set to zero on transmission + and must be ignored on receipt. + + + SC : 3 bits + Indicates the ATM Service Class. Values currently allowed are: + 0: UBR (Unspecified Bit Rate) + 1: VBR-NRT (Variable Bit Rate, Non-Real Time) + 2: VBR-RT (Variable Bit Rate, Real Time) + 3: CBR (Constant Bit Rate) + 4-7: reserved + + + + + + + +Malis & Hsiao Informational [Page 3] + +RFC 3496 ATM Service Class-aware MPLS Traffic Engineering March 2003 + + +4. Handling the ATM_SERVICECLASS Object + + To establish an LSP tunnel with RSVP-TE, the sender LSR creates a + PATH message with a session type of LSP_Tunnel_IPv4 and with a + LABEL_REQUEST object as per [RSVP-TE]. The sender LSR may also + include the DIFFSERV object as per [DIFF-MPLS]. + + If the LSP is associated with an ATM Service Class, the sender LSR + must include the ATM_SERVICECLASS object in the PATH message with the + Service-Class (SC) field set to signify the desired ATM Service + Class. + + If a path message contains multiple ATM_SERVICECLASS objects, only + the first one is meaningful; subsequent ATM_SERVICECLASS object(s) + must be ignored and must not be forwarded. + + Each LSR along the path that is ATM_SERVICECLASS-aware records the + ATM_SERVICECLASS object, when present, in its path state block. + + The destination LSR responds to the PATH message by sending a RESV + message without an ATM_SERVICECLASS object (whether the PATH message + contained an ATM_SERVICECLASS object or not). + +5. Non-support of the ATM_SERVICECLASS Object + + An LSR that does not recognize the ATM_SERVICECLASS object Class + Number must behave in accordance with the procedures specified in + [RSVP] for an unknown Class Number with the binary format 11bbbbbb, + where b=0 or 1 (i.e., RSVP will ignore the object but forward it + unexamined and unmodified). + + An LSR that recognizes the ATM_SERVICECLASS object Class Number but + does not recognize the ATM_SERVICECLASS object C-Type, must behave in + accordance with the procedures specified in [RSVP] for an unknown + C-type (i.e., it must send a PathErr with the error code 'Unknown + object C-Type' toward the sender). + + In both situations, this causes the path setup to fail. The sender + should notify management that a LSP cannot be established and + possibly might take action to retry reservation establishment without + the ATM_SERVICECLASS object. + +6. Security Considerations + + The solution is not expected to add specific security requirements + beyond those of Diff-Serv and existing TE. The security mechanisms + currently used with Diff-Serv and existing TE can be used with this + solution. + + + +Malis & Hsiao Informational [Page 4] + +RFC 3496 ATM Service Class-aware MPLS Traffic Engineering March 2003 + + +7. IANA Considerations + + The IANA has registered a new RSVP Class Number for ATM_SERVICECLASS + (227). (See http://www.iana.org/assignments/rsvp-parameters). + +8. References + + [DIFF-MPLS] Le Faucheur, F., Wu, L., Davie, B., Davari, S., Vaananen, + P., Krishnan, R., Cheval, P. and J. Heinanen, "Multi- + Protocol Label Switching (MPLS) Support of Differentiated + Services", RFC 3270, May 2002. + + [RSVP] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S. and S. + Jazmin , "Resource ReSerVation Protocol (RSVP) -- Version + 1 Functional Specification", RFC 2205, September 1997. + + [RSVP-TE] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V. + and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP + Tunnels", RFC 3209, December 2001. + + [TM] ATM Forum Traffic Management Specification Version 4.0, + af-tm-0056.000, April 1996. + +9. Authors' Addresses + + Andrew G. Malis + Vivace Networks, Inc. + 2730 Orchard Parkway + San Jose, CA 95134 + + EMail: Andy.Malis@vivacenetworks.com + + + Tony Hsiao + Vivace Networks, Inc. + 2730 Orchard Parkway + San Jose, CA 95134 + + EMail: Tony.Hsiao@VivaceNetworks.com + + + + + + + + + + + + +Malis & Hsiao Informational [Page 5] + +RFC 3496 ATM Service Class-aware MPLS Traffic Engineering March 2003 + + +10. Full Copyright Statement + + Copyright (C) The Internet Society (2003). All Rights Reserved. + + This document and translations of it may be copied and furnished to + others, and derivative works that comment on or otherwise explain it + or assist in its implementation may be prepared, copied, published + and distributed, in whole or in part, without restriction of any + kind, provided that the above copyright notice and this paragraph are + included on all such copies and derivative works. However, this + document itself may not be modified in any way, such as by removing + the copyright notice or references to the Internet Society or other + Internet organizations, except as needed for the purpose of + developing Internet standards in which case the procedures for + copyrights defined in the Internet Standards process must be + followed, or as required to translate it into languages other than + English. + + The limited permissions granted above are perpetual and will not be + revoked by the Internet Society or its successors or assigns. + + This document and the information contained herein is provided on an + "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING + TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING + BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION + HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF + MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. + +Acknowledgement + + Funding for the RFC Editor function is currently provided by the + Internet Society. + + + + + + + + + + + + + + + + + + + +Malis & Hsiao Informational [Page 6] + |