[mpls] Comments on draft-ietf-mpls-tp-cc-cv-rdi-01

[Greg Mirsky <[e-mail]>]

Dear Authors and All,
please find my comments to the document below:

·         Abstract, first paragraph s/are/the

·         Section 3. From description of CV mode it is not clear, as from
description of CC mode, whether RDI functionalities supported in CV mode.
Though description of RDI explicitly mentions that. Either mention RDI
functionality in connection to CV mode or remove it from CC for consistency.

·         Section 3.1 “It's possible to run BFD in CC mode on some transport
paths and BFD in CV mode on other transport paths.” I think that this is
important to mention only for paths between the same pair of end nodes.

·         Section 3.4 “A BFD session is enabled when the CC or proactive CV
functionality is enabled on a configured Maintenance Entity (ME) or in the
case of an associated bi-directional path, pair of Maintenance Entities”
conflicts with “A new BFD session is initiated when the operator enables or
re-enables the CC or CV functionality on the same ME” as the latter
statement refers to a single ME instance regardless whether bi-directional
path is co-routed or associated. I think that a BFD session is one-to-one
mapped with ME regardless number of MEs that used to monitor connectivity
and/or continuity of p2p bidirectional path.

·         Section 3.5, first paragraph. I think that even though BFD is
capable to change frequency of transmitting messages on a fly, in MPLS-TP
such action must go through Admin Down state as one BFD session is
effectively taken down and another, with different parameters, is enabled.

·         Section 3.5,  p.7. I think that there’s another clarification of
how MEP with zero transmit rate send its BFD control packets will be in
useful - how this MEP sends these packets. Perhaps use of ACH encapsulation
over reverse direction of the associated bi-directional path will be default
behavior. But it could be over DCN with or without IP addressing.


Regards,

Greg