Subject: [mpls-tp] Verizon's comments on draft-ietf-mpls-tp-requirements-04

From: "Andrew G. Malis" <[email-masked]>
Date: Fri, 27 Feb 2009 14:35:06 -0500

Earlier today, Verizon's transport and packet teams conducted a review
of draft-ietf-mpls-tp-requirements-04 . Our requested changes are
contained in the attached Word file, and major comments are also
summarized in this email. The Word file also contains some minor
editorial corrections, but they are not included in this summary.
I'll be using the requirement numbering in the document in this
summary. Supporting comments on the proposed changes are in
parentheses, and are not intended for the draft.

14. We found that requirement 14 contains several different
requirements combined together, and thought it would be more clear to
break these into separate requirements. While we numbered these 14A,
B, and C, we don't care if this numbering is used, or if separate
numbers are used:

14A. The MPLS-TP data plane MUST be capable of forwarding data
independent of the control or management plane used to configure and
operate the MPLS-TP layer network. If the control plane fails and does
not restart, the data plane connections MUST be held and MUST NOT time
out.

14B. The MPLS-TP data plane MUST be capable of taking recovery actions
independent of the control plane (if any) used to configure and
operate the MPLS-TP layer network.

14C.  If a control plane is used for MPLS-TP, the control plane's
graceful restart capabilities, if any, MUST be supported.

(Note that 14C is a new requirement, and came up during our discussion
of control plane restarting. It may be better placed in section 2.4,
and that's fine.)

16. We would like to add a new second sentence to this requirement. It
will now read:

16  MPLS-TP MUST support transport paths through multiple homogeneous
domains. MPLS-TP SHOULD support transport paths through multiple
non-homogeneous domains.

(We expect this to be a case that will need to be supported.)

24. We would like to add a new second sentence to this requirement. It
will now read:

24  It MUST be possible to hide MPLS-TP layer network addressing and
other information (e.g. topology) from client layers. However, it
SHOULD be possible, at the option of the operator, to leak a limited
amount of summarized information (such as SRLGs or reachability)
between layers.

33. We would like to change this requirement from a MAY to a MUST.

(We have applications, such as P2P video, where asymmetric bandwidth
will be very important.)

41. We would like to change this requirement from a SHOULD to a MUST.

(We see the independence as extremely important.)

49. We would like to add a new requirement 49D:

49D. Recovery MUST meet SLA requirements over multiple domains.

(We expect this to be an important case for us).

64. We would like to change this requirement from a MAY to a MUST.

(Why wouldn't you want to go back to the shortest or otherwise
preferred path following restoration?)

Thanks,
Andy