Subject: Re: perhaps time to check our TCP against spec?
To: Jason Thorpe <thorpej@nas.nasa.gov>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
List: tech-net
Date: 04/06/1998 22:01:39
On  "Mon, 06 Apr 1998 21:27:43 -0700",  Jason Thorpe <thorpej@nas.nasa.gov>
writes:

>On Mon, 06 Apr 1998 19:05:53 -0700 
> Jonathan Stone <jonathan@DSG.Stanford.EDU> wrote:
>
> > Yes, that, and that merely RFC-conformant hosts (or NetBSD hosts
> > without the more aggressive ACK changes) would only be ACKing2*MSS.
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

> > Which could be a heck of a lot more than twice the actual `MSS'
> > derived from the interface.

>NetBSD does not ACK every 2*rxMSS.  It ACKs every two segments received,
>regardless of size.

Right. that's the ``more aggressive ACK'' policy.
Was that too hard to follow.

And, as I said, that's a nonstandard. You can't argue it will be
applied elsewhere, like in the scenario I posted just before:

   --FDDI ring A---
       |
     Host A
       |
     --------------------------  Ethernet ----  router R
                                                  |
                                                  |
                                             --FDDI ring B---
                                                      |
                                                      |
                                                      |
                                                   Host B


Unless you get NetBSD's nonstandard more-aggressive acking into the
IETF standards track.  Which might not be a bad idea, if people deploy
ideas like in_maxmtu in situations like the one above.
Where, if things break as I think they do, it suggests the in_maxmtu
thing really has not been suifficently well thought-out.


> > Is that in 1.3.1 or not?

>If he "just committed" it, obviously it's not.

So, are you still saying ``where's the problem?'' and that
I need to get a clue?