Subject: [PWE3] [Technical Errata Reported] RFC5601 (1859)

From: RFC Errata System <[email-masked]>
Date: Wed, 9 Sep 2009 00:46:07 -0700 (PDT)

The following errata report has been submitted for RFC5601,
"Pseudowire (PW) Management Information Base (MIB)".

--------------------------------------
You may review the report below and at:
http://www.rfc-editor.org/errata_search.php?rfc=5601&eid=1859

--------------------------------------
Type: Technical
Reported by: Alfred Hoenes <[email-masked]>

Section: 12, pg.25

Original Text
-------------
[[ DESCRIPTION clause for pwFcsRetentionCfg OBJECT-TYPE ]]

         "The local configuration of Frame Check Sequence (FCS)
          retention for this PW.  FCS retention can be configured for
          PW types High-Level Data Link Control (HDLC), Point-to-Point
          Protocol (PPP), and Ethernet only.  If the implementation
|         does not support FCS retention, an error MUST be reported in
          pwFcsRetentionStatus.  This object MAY be changed only if
          the PW is not active."

Corrected Text
--------------
         "The local configuration of Frame Check Sequence (FCS)
          retention for this PW.  FCS retention can be configured for
          PW types High-Level Data Link Control (HDLC), Point-to-Point
          Protocol (PPP), and Ethernet only.  If the implementation
|         does not support requested FCS retention, an error MUST be
          reported in pwFcsRetentionStatus.
          This object MAY be changed only if the PW is not active."

Notes
-----
Rationale:

Taken literally, the original DESCRIPTION is obviously erroneous,
as it would indicate unconditional signaling of an error, whether
the activation of unsupported FCS retention is requested or not.
This would be contrary to the DESCRIPTION for pwFcsRetentionStatus.

The above change proposal aims at curing this issue with a minimal
footprint in the text; alternatively, the 3rd sentence might be
rephrased as:
                                       [...]  If the implementation
|         does not support FCS retention and pwFcsRetentionCfg is
          set to fcsRetentionEnable(2), an error MUST be reported in
          pwFcsRetentionStatus.

Note:
It is common practice (and according to the ASN.1 specifications
arguably even requireed) that the labels and numerical values
for enumerated values *not* be separated by white space.
For uniformity in the IETF and within the document, it would
therefore have been preferable to spell the SYNTAX clause of
this object,
                SYNTAX        INTEGER {
|                  fcsRetentionDisable  (1),
|                  fcsRetentionEnable   (2)
                }
as: 
                SYNTAX        INTEGER {
|                  fcsRetentionDisable(1),
|                  fcsRetentionEnable(2)
                }

Instructions:
-------------
This errata is currently posted as "Reported". If necessary, please
use "Reply All" to discuss whether it should be verified or
rejected. When a decision is reached, the verifying party (IESG)
can log in to change the status and edit the report, if necessary. 

--------------------------------------
RFC5601 (draft-ietf-pwe3-pw-mib-14)
--------------------------------------
Title               : Pseudowire (PW) Management Information Base (MIB)
Publication Date    : July 2009
Author(s)           : T. Nadeau, Ed., D. Zelig, Ed.
Category            : PROPOSED STANDARD
Source              : Pseudo Wire Emulation Edge to Edge
Area                : Internet
Stream              : IETF
Verifying Party     : IESG