--- 1/draft-ietf-mpls-crldp-applic-00.txt 2006-02-05 00:37:41.000000000 +0100 +++ 2/draft-ietf-mpls-crldp-applic-01.txt 2006-02-05 00:37:41.000000000 +0100 @@ -1,28 +1,25 @@ -MPLS Working Group Jerry Ash -Internet Draft AT&T -Expiration Date: March 2000 - Muckai Girish - SBC Technology Resources Inc. - Eric Gray - Lucent Technologies +MPLS Working Group Jerry Ash, AT&T +Internet Draft +Expiration Date: January 2001 Muckai Girish, Atoga Systems - Bilel Jamoussi - Gregory Wright + Eric Gray, Zaffire, Inc. + + Bilel Jamoussi, Gregory Wright, Nortel Networks Corp. - September 1999 + July 2000 Applicability Statement for CR-LDP - draft-ietf-mpls-crldp-applic-00.txt + draft-ietf-mpls-crldp-applic-01.txt 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. @@ -40,26 +37,27 @@ Abstract This Internet-Draft discusses the applicability of Constraint-Based LSP Setup using LDP [1]. It discusses possible network applications, extensions to Label Distribution Protocol (LDP) [2] required to implement constraint-based routing, guidelines for deployment and known limitations of the protocol. This document is a prerequisite to advancing CR-LDP on the standards track. -Jamoussi, et. al. [Page 1]Internet Draft Applicability Statement for CR-LDP September, 1999 - 1. Introduction As the Internet evolves, additional capabilities are required to ensure proper treatment of data [3], voice, video and other delay + +Jamoussi, et. al. [Page 1] Internet Draft Applicability Statement for CR-LDP July, 2000 + sensitive traffic [4]. MPLS enhances source routing and allows for certain techniques, used in circuit switching, in IP networks. This permits a scalable approach to handling these diverse transmission requirements. CR-LDP is a simple, scalable, open, non-proprietary, traffic engineering signaling protocol for MPLS IP networks. CR-LDP provides mechanisms for establishing explicitly routed Label Switched Paths (LSPs). These mechanisms are defined as extensions to LDP [1]. Because LDP is a peer-to-peer protocol based on the establishment and maintenance of TCP sessions, the following natural @@ -91,28 +89,41 @@ describe, characterize and parameterize a wide variety of QoS scenarios and services including IP differentiated services [5], integrated services [6], ATM service classes [7], and frame relay [8]. CR-LDP is designed to adequately support the various media types that MPLS was designed to support (ATM, FR, Ethernet, PPP, etc.). Hence, it will work equally well for Multi-service switched networks, router networks, or hybrid networks. -Jamoussi, et. al. March 2000 [Page 2]Internet Draft Applicability Statement for CR-LDP September, 1999 + This applicability statement does not preclude the use of other + signaling and label distribution protocols for the traffic + engineering application in MPLS based networks. Service providers + are free to deploy whatever signaling protocol meets their needs. + + In particular CR-LDP and RSVP-TE [9] are two signaling protocols + that perform similar functions in MPLS networks. There is currently + +Jamoussi, et. al. [Page 2] Internet Draft Applicability Statement for CR-LDP July, 2000 + + no consensus on which protocol is technically superior. Therefore, + network administrators should make a choice between the two based + upon their needs and particular situation. Applicability of RSVP-TE + is described in [10]. 2. Applicability of extensions to LDP - To provide for support of additional LSP services, CR-LDP extensions - are defined in such a way as to be directly translatable to objects - and messages used in other protocols defined to provide similar - services [9]. Implementations can take advantage of this fact to: + To provide support of additional LSP services, CR-LDP extensions are + defined in such a way as to be directly translatable to objects and + messages used in other protocols defined to provide similar services + [9]. Implementations can take advantage of this fact to: Setup LSPs for provision of an aggregate service associated with the services being provided via these other protocols. Directly translate protocol messages to provide services defined in a non-CR-LDP portion of the network. Describe, characterize and parameterize a wide variety of QoS scenarios and services including IP differentiated services, integrated services, ATM service classes, and frame relay. @@ -140,26 +151,27 @@ LDP specifies the following label distribution and management modes (which can be combined in various logical ways described in LDP): . Downstream On Demand label distribution . Downstream Unsolicited label distribution . Independent Label Distribution Control . Ordered Label Distribution Control . Conservative Label Retention Mode . Liberal Label Retention Mode +Jamoussi, et. al. [Page 3] Internet Draft Applicability Statement for CR-LDP July, 2000 + + The applicability of LDP is described in [11]. + In networks where only Traffic Engineered LSPs are required, the CR- LDP implementation and deployment does NOT require all the functionality defined in the LDP specification. The basic Discovery, - -Jamoussi, et. al. March 2000 [Page 3]Internet Draft Applicability Statement for CR-LDP September, 1999 - Session, and Notification messages are required. However, CR-LDP requires one specific combination of the label distribution modes: . Downstream On Demand Ordered label distribution and conservative Label Retention Mode Although CR-LDP is defined as an extension to LDP, support for Downstream Unsolicited Label Advertisement and Independent Control modes is not required for support of Strict Explicit Routes. In addition, implementations of CR-LDP MAY be able to support Loose @@ -193,79 +205,85 @@ setup. Multiple label allocations per LSP setup are FFS. 5. Security Considerations No additional security issues are introduced in this draft. As an extension to LDP, CR-LDP shares the security concerns associated with LDP. 6. Acknowledgements +Jamoussi, et. al. [Page 4] Internet Draft Applicability Statement for CR-LDP July, 2000 + The authors would like to thank the following people for their careful review of the draft and their comments: Loa Andersson, Peter Ashwood-Smith, Anoop Ghanwani, Juha Heinanen, Jon Weil, and Adrian Farrel. -Jamoussi, et. al. March 2000 [Page 4]Internet Draft Applicability Statement for CR-LDP September, 1999 - 7. References 1 B. Jamoussi, et., al., "Constraint-based LSP Setup Using LDP", - work in progress, September 1999. + work in progress, June 2000. 2 L. Andersson, et., al., "LDP Specification", work in progress, - June 1999. + June 2000. 3 D. Awduche et., al., "Requirements for Traffic Engineering Over MPLS", RFC 2702, September 1999. 4 G. Ash, et., al.,"LSP Modification using CR-LDP," work in - progress, July 1999. + progress, February 2000. 5 S. Blake et., al., "An Architecture for Differentiated Services", RFC-2495, December 1998. 6 S. Shenker, J. Wroclawski, "General Characterization Parameters for Integrated Service Network Elements" RFC-2215 7 ATM Forum Traffic Management Specification Version 4.1 (AF-TM- 0121.000), March 1999. 8 CONGESTION MANAGEMENT FOR THE ISDN FRAME RELAYING BEARER SERVICE, ITU (CCITT) Recommendation I.370, 1991. 9 D. Awduche, L. Berger, D. Gan, T. Li, G. Swallow, V. Srinivasan, - "Extensions to RSVP for LSP Tunnels," work in progress, September - 1999. + "Extensions to RSVP for LSP Tunnels," work in progress, February + 2000. + + 10 D. Awduche, A. Hannan, X. Xiao, "Applicability Statement for + Extensions to RSVP for LSP-Tunnels_, work in progress, April + 2000. + + 11 B. Thomas, E. Gray, "LDP Applicability", Work in Progress, June + 2000. + +Jamoussi, et. al. [Page 5] Internet Draft Applicability Statement for CR-LDP July, 2000 8. Author's Addresses Gerald R. Ash M. K. Girish - AT&T SBC Technology Resources, Inc. - Room MT E3-3C37 4698 Willow Road, - 200 Laurel Avenue Pleasanton, CA 94588 - Middletown, NJ 07748 USA - USA Phone: +1 925 598-1263 - Phone: 732-420-4578 Fax: +1 925 598-1322 - Fax: 732-440-6687 mgirish@tri.sbc.com + AT&T Atoga Systems + Room MT E3-3C37 49026 Milmont Drive + 200 Laurel Avenue Fremont, CA 94538 + Middletown, NJ 07748 E-mail: muckai@atoga.com + USA + Phone: 732-420-4578 + Fax: 732-440-6687 Email: gash@att.com Eric W Gray Bilel Jamoussi - Lucent Technologies, Inc. Nortel Networks Corp. - PO Box 0710 600 Technology Park Drive - Durham, NH, 03824-0710 Billerica, MA 01821 - USA USA - Phone: +1 603 659 3386 phone: +1 978-288-4506 - Ewgray@lucent.com Jamoussi@nortelnetworks.com - -Jamoussi, et. al. March 2000 [Page 5]Internet Draft Applicability Statement for CR-LDP September, 1999 - + Zaffire, Inc Nortel Networks Corp. + 2630 Orchard Parkway, 600 Technology Park Drive + San Jose, CA 95134-2020 Billerica, MA 01821 + Phone: 408-894-7362 USA + egray@zaffire.com phone: +1 978-288-4506 + Jamoussi@nortelnetworks.com Gregory Wright Nortel Networks Corp. P O Box 3511 Station C Ottawa, ON K1Y 4H7 Canada Phone: +1 613 765-7912 gwright@nortelnetworks.com Full Copyright Statement @@ -279,10 +297,12 @@ 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. + +Jamoussi, et. al. [Page 6]