[babel] Shepherd Review of draft-ietf-babel-source-specific-04

[Donald Eastlake <[e-mail]>]

Hi,

Possible technical issues:
===================
Section 6, page 7, first parenthetical:
   I think instead of "and all of its extensions" it should say something a
bit more limited. How about "and all previously standardized extensions"?

Section 7, page 8, 2nd paragraph:
   Generally, cases where different routers can interpret routing protocol
messages differently make me very nervous. It is almost always possible to
construct a situation where this causes persistent looping. It seems to me
that you need to unambiguously specify what is done if there is a malformed
TLV with multiple Source Prefix sub-TLVs. Such TLVs could always be ignored
or the first or the last Source Prefix sut-TLV could be the effective
sub-TLV with other Source Prefix sub-TLVs ignored. But whatever is
specified, it needs to be mandatory unambiguous behavior.

Section 7.1, Page 9:
   What do you do when you get a malformed Source Prefix sub-TLV with a
zero Source Plen? I guess this is answered below where it says the TLV is
ignored if the sub-TLV is malformed. (I guess it could also be malformed by
Source Plen being too large.) Perhaps it should say "This MUST NOT be 0. If
it is 0, the enclosing TLV is ignored."
   For completeness, whether the Source Prefix is left-justified or
right-justified should be specified.

Section 7.3, Page 9:
   Continuing the theme of some of the comments above, what do you do with
a wildcard request that does contain a Source Prefix sub-TLV?

Typos:
=====
Section 5.2, page 7, top line:
   "that is has" -> "that it has"

Section 7.2, Page 9, third line:
   "than" -> "as"

Minor textural comments:
===================
   These are just minor cases where I think the draft would read slightly
better with a wording change.

Abstract:
OLD
source address. This document describes an extension for source-
specific routing to the Babel routing protocol.
NEW
source address. This document describes an extension to the Babel
routing protocol for source-specific routing .

Section 1, page 3, 1st paragraph, next to last line:
   "in case of equality" -> "in case of equally specific destination
addresses"

Section 5.1, page 6, last line:
    "sub-TLV" -> "source specific sub-TLV"

Section 6.2, pag 8, first line:
   ", discarding source specific" -> ", the discarding of source-specific"

Thanks,
Donald
===============================
 Donald E. Eastlake 3rd   [phone] (cell)
 1424 Pro Shop Court, Davenport, FL 33896 USA
 [e-mail]