Re: [tcpm] Intended status of draft-ietf-tcpm-newcwv - Confirmation of discussion during IETF 89

[Mark Allman <[e-mail]>]

My high order bit here is that the newcwv document isn't in very good
shape [per previous comments] and so its a little hard to have these
conversations in that context if you ask me.  And, so I'd suggest this
arbitrary two week period is premature.

However, to give a hit on the two questions you asked ...

> In the room there was strong consensus that this document should be
> heading for Experimental status, given that further experimentation
> and operational experience with the mechanism is needed (e.g.,
> regarding pacing).

If it is the pacing that is the reason for experimental instead of
proposed I'd disagree.  Pacing makes the imposed load on the network
less aggressive than current mechanisms and so I don't see any reason to
spin at experimental.  Not that there may not be a refining of our
understanding of pacing by actually doing it, but that the possibility
of harm to the network seems pretty small to me.

Now if the reason for experimental is that newcwv is more aggressive
than the current TCP spec recommends then perhaps that is a better
reason.  However, the flip side is that we have gotten by with no
downward adjustment based on cwnd use / non-use for a long time and so
relative to that newcwv is still more conservative and hence seems fine
for proposed.

(Of course, both these are modulo that I don't really yet understand or
buy newcwv because the document has yet to convince me we need something
new and/or that the new algorithm is reasonable.  But, I do have some
trust in the involved folks and so I figure the document will probably
get there.)

> In addition, draft-ietf-tcpm-newcwv recommends (for a long time
> already) to move RFC 2861 from Experimental to Historic. According to
> the feedback in the room, the TCPM working group seems to agree on
> that. This message thus intends to confirm that obsoleting RFC 2861 is
> consensus of the TCPM working group.

I don't see this yet.  Per previous discussion with Gorry the newcwv
pertains to 'rate limited' periods, whereas RFC 2681 pertains to 'idle'
or 'application limited' periods.  The new document does not shed any
light on how these periods relate to one another.  Gorry seems to
indicate that the new version encompasses the old (and then some).  But,
I have no good understanding of this relationship myself.  I am sure I
will better grok it after the next version of the draft.  But, until we
see a cogent argument written down I don't see how we can decide whether
to obsolete RFC 2681.

Given the state of the newcwv document these questions are just
premature.  We'd be better off spending cycles on the actual meat of the
document.

allman