Liaison statement
LS173 - Comments on draft-ietf-mpls-tp-data-plane-02 [Ref # 030.02]

Submission date 2010-05-06
From ITU-T SG 15 (Greg Jones)
To IETF MPLS WG (swallow@cisco.com, loa@pi.nu)
Cc paf@cisco.com, stbryant@cisco.com, adrian.farrel@huawei.com, rcallon@juniper.net, mpls@ietf.org, yoichi.maeda@ntt-at.co.jp, steve.trowbridge@alcatel-lucent.com
Response contact tsbsg15@itu.int, greg.jones@itu.int, hiroshi.ota@itu.int
Technical contact malcolm.betts@zte.com.cn
Purpose For action
Deadline 2010-05-28 Action Taken
Attachments LS173 - Comments on draft-ietf-mpls-tp-data-plane-02 [Ref # 030.02] - pdf body
Body
Thank you for your liaison statement (Ref # 030.01) requesting a review by the
ITU-T of the MPLS-TP data plane draft.
The experts of Q.12/15 have reviewed draft-ietf-mpls-tp-data-plane-01 by
correspondence and request that the following changes are made before the IETF
approves the draft.

Section 3.1.1.  LSP Packet Encapsulation and Forwarding: Replace the fourth
paragraph: 
“Support for the Pipe and Short Pipe DiffServ tunneling and TTL processing
models described in [RFC3270] and [RFC3443] is REQUIRED by the MPLS-TP. 
Support for the Uniform model is OPTIONAL.” 
With:
“Support for the Pipe and Short Pipe DiffServ tunneling and TTL processing
models described in [RFC3270] and [RFC3443] is REQUIRED by the MPLS-TP. 
Support for the Uniform model is for REQUIRED for Diffserv tunnelling. The
Uniform model MUST NOT be used for TTL processing.”
Reason for the requested change:
The modified fourth paragraph does not fully address our comment on the -01
version which was intended to provide support for the PST application.  The
uniform model must be supported to ensure that a LSP in a PST can be
configured to have the same PHB as the LSP being monitored.  Also the uniform
model for TTL processing must not be used to avoid problems with the TTL
addressing of MIPs.

Section 6.  Security Considerations: Replace:
2.  Any MPLS label processed at the receiving LSR, such as an LSP or PW label,
has a label value that the receiving LSR has previously distributed to the
peer beyond that neighbour (i.e., when it is known that the path from the
system to which the label was distributed to the receiving system is via that
neighbour).
With:
2.  Packets that arrive on an interface or, for PW or hierarchical LSPs, LSP
with a given label value should not be forwarded unless that label value is
assigned to an LSP or PW to be carried by the peer LSR or PE over that
interface or LSP.
Reason for the requested change:
The text is confusing, the replacement text is aligned with text that was
proposed to be added to the MPLS-TP framework draft.