Subject: Editorial comments on draft-ietf-bfd-base-11

From: Jeffrey Haas <[email-masked]>
Date: Sat, 20 Mar 2010 18:20:54 +0000

Daves,

Since I had to review the MIB, I reviewed most of the base specs as well.  I
had a few comments which are very minor and perhaps worth including in an
auth48 update.

At no point in the specification is the location of the authentication section
in the BFD described.  It would be sufficient to say that it follows the
mandatory section.

There are some minor issues regarding the length field in the mdndatory
section and the authentication present bit.  This is the stuff of
conformance weenies and I suspect I know where you'll tell me to put my
comments. :-)

- If the authentication present bit is 0 and authentication is present in
  the PDU, should we ignore the authentication data even if the length of
  the BFD control packet correctly includes the optional authentication
  section?

- The mandatory section has a fixed length.  The optional authentication
  section is at least 2 bytes of data.  Length MUST accomodate the mandatory
  section plus the optional authentication section.

  Section 6.8.6 doesn't accomodate for improper authentication length.  It
  merely places a lower bound on it and an upper bound of the transport
  payload length.  Section 6.7 places checks on the authentication length but
  doesn't check against length.

  I suspect the loose wording is intended to accommodate adding arbitrary
  data *after* the optional authentication section (good for future
  extensions) but it's loose enough to not require Length be long enough to
  cover the packet contents.

  Given the thought that this is meant to accommodate future expansion, you
  may wish to consider adding wording that states that length must be long
  enough to cover the mandatory section and the optional authentication
  section.

-- Jeff