Subject: [mpls] Comments to Return Path Specified LSP Ping

From: Greg Mirsky <[email-masked]>
Date: Fri, 15 Jan 2010 14:47:28 -0800

Dear Mach,
please find my comments to draft
draft-chen-mpls-return-path-specified-lsp-ping-01.txt<http://tools.ietf.org/html/draft-chen-mpls-return-path-specified-lsp-ping-01.txt>below:

   - Section 3.2, p.5 When defining the Length field could mention that "the
   Length field MUST NOT be zero".
   - In the last paragraph on p.5 stress that RP TLV can have one or more
   nested sub-TLVs. "It MUST have one or more nested sub-TLVs that describe the
   specified paths the echo reply message is required to follow."

   - Section 3.3.1, p.7  would propose to rename "MUST be zero" in the Flag
   field into "Reserved" with addition of following wording:

"where Reserved MUST be set to 0 on Send and ignored on Receive".

   - Section 3.3.2, p.8 Use of IPv4 in the first sentence ("The IPv4 RSVP
   Tunnel sub-TLV ...") in the context of this section looks as typo.
   - Section 3.3.4 describes Any Candidate sub-TLV as indication of
   exclusion from consideration by egress LSR of all LSPs. But option 5 in
   Section 3.3 implies that the Any Candidate sub-TLV can be used in
   conjunction with sub-TLVs defined in RFC4379 or newly defined, excluding
   itself of course, to provide explicit list of LSPs to be excluded by the
   egress LSP from consideration as the return path for LSP Ping. This use
   scenario can be mentioned in the Section to clarify: "If there is only an
   Any Candidate sub-TLV included in the echo request (i.e., no other sub-TLVs
   are present in the RP TLV) ..." description. (This use case is mentioned in
   Section 4.2 p.11 though).

Kind regards,
Greg

---

From: Mach Chen <[email-masked]>
Date: Mon, 18 Jan 2010 10:01:31 +0800

Dear Greg,

Thanks for your comments!

Please see inline...

--------------------------------------------------
From: "Greg Mirsky" <[email-masked]>
Sent: Saturday, January 16, 2010 6:47 AM
To: "Mach Chen" <[email-masked]>; <[email-masked]>
Subject: Comments to Return Path Specified LSP Ping

>   specified paths the echo reply message is required to follow."

Yes, it MUST NOT be zero, will add text for clarification in the next 
revision.

> "where Reserved MUST be set to 0 on Send and ignored on Receive".

OK, it's better to change to "Reserved" for new extension, will do that.

>   Tunnel sub-TLV ...") in the context of this section looks as typo.

Yes, it should be IPv6, good catch!

>   Section 4.2 p.11 though).

OK, will clarify this in the next revision.

Best regards,
Mach