Subject: [mpls] [Errata Verified] RFC7110 (4195)

From: RFC Errata System <[email-masked]>
Date: Tue, 9 Dec 2014 11:04:47 -0800 (PST)

The following errata report has been verified for RFC7110,
"Return Path Specified Label Switched Path (LSP) Ping". 

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You may review the report below and at:
http://www.rfc-editor.org/errata_search.php?rfc=7110&eid=4195

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Status: Verified
Type: Editorial

Reported by: tom petch <[email-masked]>
Date Reported: 2014-12-09
Verified by: Adrian Farrel (IESG)

Section: 5.4

Original Text
-------------
When an echo reply is received, if the Reply Mode is "Reply via
Specified Path" and the Reply Path return code is "The echo reply was
sent successfully using the specified Reply Path", and if the return
path is an MPLS LSP.  The ingress LSR MUST perform FEC validation
(based on the FEC Stack information of the return path carried in the
Reply Path TLV) as an egress LSR does when receiving an echo request,
the FEC validation process (relevant to "ping" mode) defined in
Section 4.4.1 of [RFC4379] applies here.

When an echo reply is received with return code set to "Malformed
echo request received" and the Subcode set to zero.  It is possible
that the egress LSR may not know the "Reply via Specified Path" Reply
Mode, the operator may choose to re-perform another LSP ping by using
one of the four Reply Modes defined [RFC4379].

Corrected Text
--------------
When an echo reply is received, if the Reply Mode is "Reply via
Specified Path" and the Reply Path return code is "The echo reply was
sent successfully using the specified Reply Path", and if the return
path is an MPLS LSP, the ingress LSR MUST perform FEC validation
(based on the FEC Stack information of the return path carried in the
Reply Path TLV) as an egress LSR does when receiving an echo request,
the FEC validation process (relevant to "ping" mode) defined in
Section 4.4.1 of [RFC4379] applies here.

When an echo reply is received with return code set to "Malformed
echo request received" and the Subcode set to zero, it is possible
that the egress LSR may not know the "Reply via Specified Path" Reply
Mode; the operator may choose to re-perform another LSP ping by using
one of the four Reply Modes defined in [RFC4379].

Notes
-----
In the first two paragraphs of section 5.4, the conditional clauses and the main clause have been separated by periods, not commas, which creates uncertainty as to whether or not text of the main clause has been elided.  This changes the periods into commas.

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RFC7110 (draft-ietf-mpls-return-path-specified-lsp-ping-15)
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Title               : Return Path Specified Label Switched Path (LSP) Ping
Publication Date    : January 2014
Author(s)           : M. Chen, W. Cao, S. Ning, F. Jounay, S. Delord
Category            : PROPOSED STANDARD
Source              : Multiprotocol Label Switching
Area                : Routing
Stream              : IETF
Verifying Party     : IESG