As a generic observation: the document seems to include some of much the
same material as draft-ietf-dnsop-ipv6-issues-11.txt (specifically, its
appendix B).

If folks think it would be a good idea, some or most of the
stuff in that draft's appendix could be moved here -- as it has a lot of
already IESG-reviewed material on additional section processing.

Notes below show some issues which also came up (in one form or another)
during dnsop-ipv6-issues.  This leads me to think the text needs significant
edits and/or merging/copying form dnsop-ipv6-issues appendix B.


   2.2. If the total response size would exceed 512 octets, and if the data
   that would not fit belonged in the question, answer, or authority
   section, then the TC bit will be set (indicating truncation) which may
   cause the requestor to retry using TCP, depending on what information
   was desired and what information was omitted.  If a retry using TCP is
   needed, the total cost of the transaction is much higher.  (See [RFC1123
   6.1.3.2] for details on the protocol requirement that UDP be attempted
   before falling back to TCP.)

==> "which _may_ cause the requestor..." is incompliant with RFC2181, which
requires that if TC is set, the whole response must be discarded, and then
you retry with TCP.  (Whether or not that's efficient or robust is a
different argument, I guess, but that's what the specs mandate.)

   2.3. RRsets are never sent partially unless truncation occurs, in which
   case the final apparent RRset in the final nonempty section must be
   considered "possibly damaged".  [...]

==> this may require a bit of rewording, as above, as the spec says to
discard the response if TC was set no matter what.

  2.6. Average and maximum question section sizes can be predicted by the
   zone owner, since they will know what names actually exist, and can
   measure which ones are queried for most often.  For cost and performance
   reasons, the majority of requests should be satisfied without truncation
   or TCP retry.

==> as above, "truncation or TCP retry" should maybe be "truncation and
TCP retry"

   2.9. The best case is no truncation.  This is because many requestors
   will retry using TCP by reflex, or will automatically re-query for
   RRsets that are "possibly truncated", without considering whether the
   omitted data was actually necessary.

==> as above, not having such "reflexes" would be against RFC2181


--
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings
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