Tech-invite3GPPspaceIETF RFCsSIP
9190898887868584838281807978777675747372717069686766656463626160595857565554535251504948474645444342414039383736353433323130292827262524232221201918171615141312111009080706050403020100
in Index   Prev   Next

RFC 6829

Label Switched Path (LSP) Ping for Pseudowire Forwarding Equivalence Classes (FECs) Advertised over IPv6

Pages: 8
Obsoleted by:  8029
Updates:  4379

ToP   noToC   RFC6829 - Page 1
Internet Engineering Task Force (IETF)                           M. Chen
Request for Comments: 6829                  Huawei Technologies Co., Ltd
Updates: 4379                                                     P. Pan
Category: Standards Track                                       Infinera
ISSN: 2070-1721                                             C. Pignataro
                                                                R. Asati
                                                                   Cisco
                                                            January 2013


                   Label Switched Path (LSP) Ping for
 Pseudowire Forwarding Equivalence Classes (FECs) Advertised over IPv6

Abstract

The Multiprotocol Label Switching (MPLS) Label Switched Path (LSP) Ping and traceroute mechanisms are commonly used to detect and isolate data-plane failures in all MPLS LSPs, including LSPs used for each direction of an MPLS Pseudowire (PW). However, the LSP Ping and traceroute elements used for PWs are not specified for IPv6 address usage. This document extends the PW LSP Ping and traceroute mechanisms so they can be used with PWs that are set up and maintained using IPv6 LDP sessions. This document updates RFC 4379. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc6829.
ToP   noToC   RFC6829 - Page 2
Copyright Notice

   Copyright (c) 2013 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Pseudowire IPv4 Target FEC Stack Sub-TLVs . . . . . . . . . . . 3 3. Pseudowire IPv6 Target FEC Stack Sub-TLVs . . . . . . . . . . . 4 3.1. FEC 128 Pseudowire . . . . . . . . . . . . . . . . . . . . 4 3.2. FEC 129 Pseudowire . . . . . . . . . . . . . . . . . . . . 5 4. Summary of Changes . . . . . . . . . . . . . . . . . . . . . . 6 5. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6 7. Security Considerations . . . . . . . . . . . . . . . . . . . . 7 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 7 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7 9.1. Normative References . . . . . . . . . . . . . . . . . . . 7 9.2. Informative References . . . . . . . . . . . . . . . . . . 7

1. Introduction

Multiprotocol Label Switching (MPLS) Label Switched Path (LSP) Ping and traceroute are defined in [RFC4379]. These mechanisms can be used to detect data-plane failures in all MPLS LSPs, including Pseudowires (PWs). However, the PW LSP Ping and traceroute elements are not specified for IPv6 address usage. Specifically, the PW Forwarding Equivalence Class (FEC) sub-TLVs for the Target FEC Stack in the LSP Ping and traceroute mechanism are defined only for IPv4 Provider Edge (PE) routers and are not applicable for the case where PEs use IPv6 addresses. Three PW- related Target FEC sub-TLVs are currently defined (FEC 128 Pseudowire-Deprecated, FEC 128 Pseudowire-Current, and FEC 129 Pseudowire, see Sections 3.2.8 through 3.2.10 of [RFC4379]). These sub-TLVs contain the source and destination addresses of the LDP session, and currently only an IPv4 LDP session is covered. Despite
ToP   noToC   RFC6829 - Page 3
   the fact that the PE IP address family is not explicit in the sub-TLV
   definition, this can be inferred indirectly by examining the lengths
   of the Sender's/Remote PE Address fields or calculating the length of
   the sub-TLVs (see Section 3.2 of [RFC4379]).  When an IPv6 LDP
   session is used, these existing sub-TLVs cannot be used since the
   addresses will not fit.  Additionally, all other sub-TLVs are defined
   in pairs, one for IPv4 and another for IPv6, but not the PW sub-TLVs.

   This document updates [RFC4379] to explicitly constrain the existing
   PW FEC sub-TLVs for IPv4 LDP sessions and extends the PW LSP Ping to
   IPv6 LDP sessions (i.e., when IPv6 LDP sessions are used to signal
   the PW, the Sender's and Receiver's IP addresses are IPv6 addresses).
   This is done by renaming the existing PW sub-TLVs to indicate "IPv4"
   and also by defining two new Target FEC sub-TLVs (FEC 128 Pseudowire
   IPv6 sub-TLV and FEC 129 Pseudowire IPv6 sub-TLV) to extend the
   application of PW LSP Ping and traceroute to IPv6 usage when an IPv6
   LDP session [MPLS-LDP] is used to signal the Pseudowire.  Note that
   FEC 128 Pseudowire (Deprecated) is not defined for IPv6 in this
   document.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

2. Pseudowire IPv4 Target FEC Stack Sub-TLVs

This document updates Section 3.2 and Sections 3.2.8 through 3.2.10 of [RFC4379] as follows and as indicated in Sections 4 and 6. This is done to avoid any potential ambiguity and confusion and to clarify that these TLVs carry only IPv4 addresses. Note that the changes are limited to the names of fields; there are no semantic changes. Sections 3.2.8 through 3.2.10 of [RFC4379] list the PW sub-TLVs and state: "FEC 128" Pseudowire (Deprecated) "FEC 128" Pseudowire "FEC 129" Pseudowire These names and titles are now changed to: "FEC 128" Pseudowire - IPv4 (Deprecated) "FEC 128" Pseudowire - IPv4 "FEC 129" Pseudowire - IPv4
ToP   noToC   RFC6829 - Page 4
   Additionally, when referring to the PE addresses, Sections 3.2.8
   through 3.2.10 of [RFC4379] state:

      Sender's PE Address

      Remote PE Address

   These are now updated to say:

      Sender's PE IPv4 Address

      Remote PE IPv4 Address

3. Pseudowire IPv6 Target FEC Stack Sub-TLVs

3.1. FEC 128 Pseudowire

The FEC 128 Pseudowire IPv6 sub-TLV has a structure consistent with the FEC 128 Pseudowire sub-TLV as described in Section 3.2.9 of [RFC4379]. The encoding of the FEC 128 Pseudowire IPv6 sub-TLV is as follows: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | FEC 128 PW IPv6 Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Sender's PE IPv6 Address ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Remote PE IPv6 Address ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PW ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PW Type | Must Be Zero | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: FEC 128 Pseudowire - IPv6 FEC 128 PW IPv6 Type: 24. 2 octets. Length: Defines the length in octets of the value field of the sub- TLV and its value is 38. 2 octets. Sender's PE IPv6 Address: The source IP address of the target IPv6 LDP session. 16 octets. Remote PE IPv6 Address: The destination IP address of the target IPv6 LDP session. 16 octets.
ToP   noToC   RFC6829 - Page 5
   PW ID: Same as FEC 128 Pseudowire IPv4 [RFC4379].

   PW Type: Same as FEC 128 Pseudowire IPv4 [RFC4379].

3.2. FEC 129 Pseudowire

The FEC 129 Pseudowire IPv6 sub-TLV has a structure consistent with the FEC 129 Pseudowire sub-TLV as described in Section 3.2.10 of [RFC4379]. The encoding of FEC 129 Pseudowire IPv6 is as follows: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | FEC 129 PW IPv6 Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Sender's PE IPv6 Address ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Remote PE IPv6 Address ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PW Type | AGI Type | AGI Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ AGI Value ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | AII Type | SAII Length | SAII Value | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ SAII Value (continued) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | AII Type | TAII Length | TAII Value | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ TAII Value (continued) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TAII (cont.) | 0-3 octets of zero padding | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: FEC 129 Pseudowire - IPv6 FEC 129 PW IPv6 Type: 25. 2 octets. Length: Defines the length in octets of the value field of the sub- TLV. 2 octets The length of this TLV is 40 + AGI (Attachment Group Identifier) length + SAII (Source Attachment Individual Identifier) length + TAII (Target Attachment Individual Identifier) length. Padding is used to make the total length a multiple of 4; the length of the padding is not included in the Length field.
ToP   noToC   RFC6829 - Page 6
   Sender's PE IPv6 Address: The source IP address of the target IPv6
   LDP session. 16 octets.

   Remote PE IPv6 Address: The destination IP address of the target IPv6
   LDP session. 16 octets.

   The other fields are the same as FEC 129 Pseudowire IPv4 [RFC4379].

4. Summary of Changes

Section 3.2 of [RFC4379] tabulates all the sub-TLVs for the Target FEC Stack. Per the change described in Sections 2 and 3, the table would show the following: Sub-Type Length Value Field -------- ------ ----------- ... 9 10 "FEC 128" Pseudowire - IPv4 (Deprecated) 10 14 "FEC 128" Pseudowire - IPv4 11 16+ "FEC 129" Pseudowire - IPv4 ... 24 38 "FEC 128" Pseudowire - IPv6 25 40+ "FEC 129" Pseudowire - IPv6

5. Operation

This document does not define any new procedures. The process described in [RFC4379] MUST be used.

6. IANA Considerations

IANA has made the following assignments in the "Multi-Protocol Label Switching (MPLS) Label Switched Paths (LSPs) Ping Parameters" registry. The following sub-TLV changes, which comprise three updates and two additions, are made for the TLV Type 1 "Target FEC Stack" in the "TLVs and sub-TLVs" sub-registry. The names of the Value fields of these three Sub-TLVs have been updated to include the "IPv4" qualifier (see Section 2), and the Reference has been updated to point to this document: Type Sub-Type Value Field ---- -------- ----------- 1 9 "FEC 128" Pseudowire - IPv4 (Deprecated) 1 10 "FEC 128" Pseudowire - IPv4 1 11 "FEC 129" Pseudowire - IPv4
ToP   noToC   RFC6829 - Page 7
   Two new entries for the Sub-Type field of the Target FEC TLV (see
   Section 3) have been created:

   Type       Sub-Type        Value Field
   ----       --------        -----------
      1           24          "FEC 128" Pseudowire - IPv6
      1           25          "FEC 129" Pseudowire - IPv6

7. Security Considerations

This document does not introduce any new security issues; the security mechanisms defined in [RFC4379] apply here.

8. Acknowledgements

The authors gratefully acknowledge the review and comments of Vanson Lim, Tom Petch, Spike Curtis, Loa Andersson, and Kireeti Kompella.

9. References

9.1. Normative References

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label Switched (MPLS) Data Plane Failures", RFC 4379, February 2006.

9.2. Informative References

[MPLS-LDP] Asati, R., Manral, V., Papneja, R., and C. Pignataro, "Updates to LDP for IPv6", Work in Progress, June 2012.
ToP   noToC   RFC6829 - Page 8

Authors' Addresses

Mach(Guoyi) Chen Huawei Technologies Co., Ltd No. 3 Xinxi Road, Shang-di, Hai-dian District Beijing 100085 China EMail: mach@huawei.com Ping Pan Infinera US EMail: ppan@infinera.com Carlos Pignataro Cisco Systems 7200-12 Kit Creek Road Research Triangle Park, NC 27709 US EMail: cpignata@cisco.com Rajiv Asati Cisco Systems 7025-6 Kit Creek Road Research Triangle Park, NC 27709 US EMail: rajiva@cisco.com