rfc-6829

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

M. Chen, P. Pan, C. Pignataro, R. Asati

date2013-01 streamIETF areartg wgmpls statusPROPOSED STANDARD pages8 canonicalhttps://www.rfc-editor.org/rfc/rfc6829 doi10.17487/RFC6829

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. [STANDARDS-TRACK]

obsoleted by

rfc-8029 — Detecting Multiprotocol Label Switched (MPLS) Data-Plane Failures

updates

rfc-4379 — Detecting Multi-Protocol Label Switched (MPLS) Data Plane Failures

Extracted elements (10)

design-rationale §1

Existing PW FEC sub-TLVs (FEC 128 Deprecated, FEC 128 Current, FEC 129) were defined only for IPv4 LDP sessions; when an IPv6 LDP session is used the 128-bit IPv6 addresses do not fit in the 32-bit address fields. All other Target FEC sub-TLVs are defined in pairs (IPv4 and IPv6), but PW sub-TLVs were not, motivating two new sub-TLVs.

mpls, ip

design-rationale §2

The PE address family could previously only be inferred indirectly by examining the lengths of the Sender's/Remote PE Address fields or calculating the length of the sub-TLVs, rather than being explicit in the sub-TLV definition. This ambiguity is resolved by renaming the existing sub-TLVs to include an 'IPv4' qualifier with no semantic changes.

mpls, ip

interoperability-note §1

FEC 128 Pseudowire (Deprecated) is not extended to IPv6 in this document; only FEC 128 Pseudowire (Current) and FEC 129 Pseudowire receive new IPv6 counterparts.

mpls, ip

normative-requirement §5 MUST

This document defines no new procedures; the process described in RFC 4379 MUST be used when operating PW LSP Ping and traceroute with the new IPv6 sub-TLVs.

mpls, ip

protocol-element §3.1

The FEC 128 Pseudowire IPv6 sub-TLV (type 24) carries the source and destination IPv6 addresses of the target LDP session, a 32-bit PW ID, and a 16-bit PW Type. Its fixed length is 38 octets.

mpls, ip

protocol-element §3.2

The FEC 129 Pseudowire IPv6 sub-TLV (type 25) carries Sender's and Remote PE IPv6 addresses (16 octets each), PW Type, and variable-length AGI, SAII, and TAII fields. The minimum fixed portion is 40 octets; padding to a 4-octet boundary is required but not included in the Length field.

mpls, ip

registry §6

IANA updated the 'TLVs and sub-TLVs' sub-registry of the 'MPLS LSP Ping Parameters' registry: sub-types 9, 10, and 11 were renamed to include the 'IPv4' qualifier, and two new sub-types were added: 24 ('FEC 128 Pseudowire – IPv6') and 25 ('FEC 129 Pseudowire – IPv6') under TLV Type 1 (Target FEC Stack).

mpls, registry, ip

security-consideration §7

This document introduces no new security issues; all security mechanisms defined in RFC 4379 apply without modification to the IPv6 PW LSP Ping extensions.

mpls, security

wire-format §3.1

FEC 128 Pseudowire IPv6 sub-TLV encoding: FEC 128 PW IPv6 Type (2 octets, value 24), Length (2 octets, value 38), Sender's PE IPv6 Address (16 octets), Remote PE IPv6 Address (16 octets), PW ID (4 octets), PW Type (2 octets), Must Be Zero (2 octets).

mpls, ip

wire-format §3.2

FEC 129 Pseudowire IPv6 sub-TLV encoding: FEC 129 PW IPv6 Type (2 octets, value 25), Length (2 octets), Sender's PE IPv6 Address (16 octets), Remote PE IPv6 Address (16 octets), PW Type (2 octets), AGI Type/Length/Value, SAII Type/Length/Value, TAII Type/Length/Value, 0–3 octets zero padding (not counted in Length).

mpls, ip