[e2e] TCP un-friendly congestion control

[Richard Carlson]

As chair of the Internet 2 Land Speed Record judging committee, I can 
confirm that TCP over long fat networks is not hopeless.  The last 2 
records, using IPv4 and IPv6, show that hosts can push the network to the 
limit.  For the latest IPv4 record a team from the US and Europe ran Iperf 
for 3700 seconds (yes just over 1 hour) between 2 PC's with 10 Gigabit 
Ethernet NICs.  They achieved a throughput rate of 2.3 Gbps, with the 
connection being limited by a transatlantic OC-48 link.  The latest IPv6 
record is being processed now, but it is equally impressive.  See the 
I2-LSR web page http://lsr.internet2.net for details.

Another thing to consider, Les Cottrell from SLAC ran some tests with these 
10 Gig NICs and tested the standard Linux 2.4 TCP, FAST TCP, HPTCP, and one 
other high performance implementation.  These tests showed no difference 
between any of the TCP implementations over 1 particular network path.  If 
Les is on this list maybe he can provide a pointer to these results.

Rich

At 05:26 PM 6/6/03 -0400, Craig Partridge wrote:

>In message <20030606140028.A59651 at xorpc.icir.org>, Luigi Rizzo writes:
>
> >exactly -- that's the whole point, the packet rate is so high that
> >there are many chances to have occasional losses anywhere in the
> >system, not just due to the channel but even because of operating
> >system issues on some of the intermediate boxes or end nodes.
>
>OK, let me get on my high horse here for a moment.
>
>The original poster asserted that in an environment where the network
>went at 1 Gbps and had 50ms of delay, TCP was hopeless.
>
>The point I was trying to drive home is that it is not hopeless.  That
>you have to define the environment far more carefully before you assert
>that TCP can or cannot do the job.  One of my frustrations these days is
>people who fail to be careful.  I was trying to encourage care in the
>problem statement.
>
>Thanks!
>
>Craig

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Richard A. Carlson                              e-mail: RACarlson at anl.gov
Network Research Section                        phone:  (630) 252-7289
Argonne National Laboratory                     fax:    (630) 252-4021
9700 Cass Ave. S.
Argonne,  IL 60439