--- 1/draft-ietf-mpls-te-scaling-analysis-04.txt 2008-12-14 16:12:02.000000000 +0100 +++ 2/draft-ietf-mpls-te-scaling-analysis-05.txt 2008-12-14 16:12:03.000000000 +0100 @@ -1,20 +1,20 @@ Network Working Group S. Yasukawa Internet-Draft NTT Intended Status: Informational A. Farrel -Created: December 2, 2008 Old Dog Consulting -Expires: June 2, 2009 O. Komolafe +Created: December 14, 2008 Old Dog Consulting +Expires: June 14, 2009 O. Komolafe Cisco Systems An Analysis of Scaling Issues in MPLS-TE Core Networks - draft-ietf-mpls-te-scaling-analysis-04.txt + draft-ietf-mpls-te-scaling-analysis-05.txt Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. 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. @@ -89,21 +89,21 @@ 8.5 Issues with MP2P LSPs ........................................ 33 9. Combined Models ............................................... 34 10. An Alternate Solution ........................................ 35 10.1 Pros and Cons of the Alternate Solution ..................... 36 11. Management Considerations .................................... 37 12. Security Considerations ...................................... 37 13. Recommendations .............................................. 38 14. IANA Considerations .......................................... 38 15. Acknowledgements ............................................. 38 16. Intellectual Property Consideration .......................... 39 - 17. Normative References ......................................... 39 + 17. Normative References ......................................... 40 18. Informative References ....................................... 40 19. Authors' Addresses ........................................... 41 1. Introduction Network operators and service providers are examining scaling issues as they look to deploy ever-larger traffic engineered Multiprotocol Label Switching (MPLS-TE) networks. Concerns have been raised about the number of Label Switched Paths (LSPs) that need to be supported at the edge and at the core of the network. The impact on control @@ -165,20 +165,33 @@ of 'duplicate' LSPs. This issue is not addressed in this document. It should also be understood that certain deployment models where separate traffic engineered LSPs are used to provide different services such as layer 3 VPNs [RFC4110] or pseudowires [RFC3985], or different classes of service [RFC3270], may result in 'duplicate' or 'parallel' LSPs running between any pair of provider edge nodes (PEs). This scaling factor is also not considered in this document, but may be easily applied as a linear factor by the reader. + The operation of security mechanisms in MPLS-TE networks [MPLS-SEC] + may have an impact on the ability of the network to scale. For + example, they may increase both the size and number of control plane + messages. Additionally, they may increase the processing overhead as + control plane messages are subject to processing algorithms (such as + encryption), and security keys need to be managed. Deployers will + need to consider the trade-offs between scaling objectives and + security objectives in thier networks and should resist the + temptation to respond to a degradation of scaling performance by + turning off security techniques that have previously been deemed as + necessary. Further analysis of the effects of security measures on + scalability are not considered further in this document. + This document is designed to help service providers discover whether existing protocols and implementations can support the network sizes that they are planning. To do this, it presents an analysis of some of the scaling concerns for MPLS-TE core networks, and examines the value of two techniques for improving scaling. This should motivate the development of appropriate deployment techniques and protocol extensions to enable the application of MPLS-TE in large networks. This document only considers the question of achieving scalability for the support of point-to-point MPLS-TE LSPs. Point-to-multipoint @@ -1822,20 +1835,25 @@ yet-to-be-defined signaling protocol extensions and are subject to the security provided by those extensions. Note that we are talking about tunneling techniques used within the network and both approaches are vulnerable to the creation of bogus tunnels that deliver data to an egress or consume network resources. The fact that the MP2P technique may prove harder to debug through OAM methods than the FA LSP approach is a security concern since it is important to be able to detect misconnections. + General issues of the realtionship between scaling and security are + covered in Section 1.1, but the details are beyond the scope of this + document. Readers are refered to [MPLS-SEC] for details of MPLS + security techniques. + 13. Recommendations The analysis in this document suggests that the ability to signal MP2P MPLS-TE LSPs is a desirable addition to the operator's MPLS-TE toolkit. At this stage, no further recommendations are made, but it would be valuable to consult more widely to discover: - The concerns of other service providers with respect to network @@ -1858,22 +1876,22 @@ adopted. 14. IANA Considerations This document makes no requests for IANA action. 15. Acknowledgements The authors are grateful to Jean-Louis Le Roux for discussions and review input. Thanks to Ben Niven-Jenkins, JP Vasseur, Loa Andersson, - and Anders Gavler for their comments. Thanks to Dave Allen for useful - discussion of the maths. + Anders Gavler, and Tom Polk for their comments. Thanks to Dave Allen + for useful discussion of the math. 16. Intellectual Property Consideration The IETF Trust takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in any IETF Document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. @@ -1953,20 +1971,24 @@ RFC 4972, July 2007. [RFC5036] Andersson, L., Doolan, P., Feldman, N., Fredette, A., and B. Thomas, "LDP Specification", RFC 5036, October 2007. [MP2P-RSVP] Yasukawa, Y., "Supporting Multipoint-to-Point Label Switched Paths in Multiprotocol Label Switching Traffic Engineering", draft-yasukawa-mpls-mp2p-rsvpte, work in progress. + [MPLS-SEC] Fang, L. (Ed.), "Security Framework for MPLS and GMPLS + Networks", draft-ietf-mpls-mpls-and-gmpls-security- + framework, work in progress. + 19. Authors' Addresses Seisho Yasukawa NTT Corporation 9-11, Midori-Cho 3-Chome Musashino-Shi, Tokyo 180-8585 Japan Phone: +81 422 59 4769 EMail: s.yasukawa@hco.ntt.co.jp Adrian Farrel