[tcpinc] Adam Roach's Yes on draft-ietf-tcpinc-tcpeno-13: (with COMMENT)

[Adam Roach <[e-mail]>]

Adam Roach has entered the following ballot position for
draft-ietf-tcpinc-tcpeno-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/iesg/statement/discuss-criteria.html
for more information about IESG DISCUSS and COMMENT positions.


The document, along with other ballot positions, can be found here:
https://datatracker.ietf.org/doc/draft-ietf-tcpinc-tcpeno/



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

Thanks for a well-thought-out and well written document. I'm looking forward to
seeing how this experiment goes. I have a few minor comments for possible
improvements.

Section 4 indicates that applications can be made aware of whether TCP
encryption is occurring:

   o  A bit available to higher-layer protocols at each endpoint for
      out-of-band negotiation of updated behavior in the presence of TCP
      encryption.

I see that this is used to bind the TEP to certain TCP-ENO information, which
is obviously good -- but I think some guidance in here cautioning about the
hazards of exposing opportunistically encrypted connections to users as
"secure" would be helpful. In general, because of the MITM considerations that
are already covered, conveying opportunistic encryption to users as "secure" is
dangerous.

Section 4.2:
   b
      The passive role bit MUST be 1 for all passive openers.  For
      active openers, it MUST default to 0, but implementations MUST
      provide an API through which an application can explicitly set "b
      = 1" before initiating an active open.  (Manual configuration of
      "b" is only necessary to enable encryption with a simultaneous
      open.)

I think this could be made clearer (thinking in particular of Spencer's
question) if this text indicated that implementations making use of
simultaneous open need to have some out-of-band negotiation of role before the
TCP connection is attempted.