[DNSOP] Erik Kline's Yes on draft-ietf-dnsop-dns-tcp-requirements-13: (with COMMENT)

[Erik Kline via Datatracker <[e-mail]>]

Erik Kline has entered the following ballot position for
draft-ietf-dnsop-dns-tcp-requirements-13: Yes

When responding, please keep the subject line intact and reply to all
email addresses included in the To and CC lines. (Feel free to cut this
introductory paragraph, however.)


Please refer to https://www.ietf.org/blog/handling-iesg-ballot-positions/
for more information about how to handle DISCUSS and COMMENT positions.


The document, along with other ballot positions, can be found here:
https://datatracker.ietf.org/doc/draft-ietf-dnsop-dns-tcp-requirements/



----------------------------------------------------------------------
COMMENT:
----------------------------------------------------------------------

[abstract vs. S1/S3, question]

* The abstract says:

   "...strongly
   encourages the operational practice of permitting DNS messages to be
   carried over TCP"

  while section 1 says:

   "...all DNS resolvers and recursive
   servers MUST support and service both TCP and UDP queries"

  and section 3 also some MUST text.

  Should the abstract be updated to say MUST rather than just
  "strongly encourages", or is there a subtly in here I'm missing?

[S4.1, comment]

* "Resolvers and other DNS clients should be aware that some servers
   might not be reachable over TCP.  For this reason, clients MAY want
   to track and limit the number of TCP connections and connection
   attempts to a single server."

  I think the same comment could be made about paths to a server from
  a given network, e.g., in the case of one network filtering TCP/53 for
  some reason.

  I'm not sure how to best reword this to add a per-network notion to
  TCP connection success tracking, but I did want to note that a mobile
  client's measure of TCP connection success to a single server might
  vary from network to network.  (for your consideration)