Re: [tcpm] I-D Action: draft-nishida-tcpm-agg-syn-ext-01.txt

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Hi Yoshi,

I just wanted to record my comment on list too:

For the aggregated option I would like to also see some of the commonly
used parameters (e.g. MSS, Window Scale) to be rolled into this.
Ideally, in some not-too-distant future, all Hosts should be supporting
this aggregated option, and retaining the additional space for those
parameters and their tcp option encoding appears to be excessive.

Especially as not the full range is used (window scale may receive a
final boost to use 0..15 instead of 0..14 currently, thus a 4-bit field
suffices; timestamp in the SYN could be abbreviated (no ECR field
needed, as the proposal for granularity signalling never got much
traction); MSS could be compressed to few commonly encountered values
(e.g. 1200, 1300, 1460, 8960, 65535 (lo0), or some variant of an
exponential encoding).

Martin's suggestion of adding in this early stage various competing
proposals into the same draft, and working out the pro/cons over time
also sounds appealing.

Finally, there are (currently) more exotic options, which are heavy
consumers of SYN tcp option space (MPTCP, TFO, MD5 / AO - with those two
really having a limited applicability domain currently). A quick rundown
of them all, and their requirements on the SYN and SYN,ACK space may be
valuable to have in the draft for discussion purposes (avoid having to
chase them when reading the draft).

Best regards,
    Richard