Re: Lossy cogent p2p experiences?

[Masataka Ohta <mohta () necom830 hpcl titech ac jp>]

William Herrin wrote:

> > No, not at all. First, though you explain slow start,
> > it has nothing to do with long fat pipe. Long fat
> > pipe problem is addressed by window scaling (and SACK).
>
> So, I've actually studied this in real-world conditions and TCP
> behaves exactly as I described in my previous email for exactly the
> reasons I explained.

Yes of course, which is my point. Your problem is that your
point of slow start has nothing to do with long fat pipe.

> Window scaling and SACK makes it possible for TCP to grow to consume
> the entire whole end-to-end pipe when the pipe is at least as large as
> the originating interface and -empty- of other traffic.

Totally wrong.

Unless the pipe is long and fat, a plain TCP without window scaling
or SACK is to grow to consume the entire whole end-to-end pipe when
the pipe is at least as large as the originating interface and
-empty- of other traffic.

> Those
> conditions are rarely found in the real world.

It is usual that TCP consumes all the available bandwidth.

Exceptions, not so rare in the real world, are plain TCPs over
long fat pipes.

                                        Masataka Ohta