wanted: wireless magic tricks

Thu Aug 16 18:00:24 UTC 2001

> Well, that is quite wonderful, but when I approached this problem
> with a collegue of mine over a sat link for a client that wasn't
> our experience and after considerable tweaking we ended up having
> to settle for less.
> 
> PS: got pointers to documents detailing the 500mbps over OC-12 sat link?
>     email addr will do, as well, I'd love to find out what they did.

Yep, sorry -- I should have included a pointer.  Try:

    David E. Brooks, Craig Buffinton, Dave R. Beering, Arun Welch,
    William D. Ivancic, Mike Zernic, Douglas J. Hoder. ACTS 118x
    Final Report High Speed TCP Interoperability Testing, July 1999.
    http://ctd.grc.nasa.gov/5610/publications/TM-1999-209272.pdf

In the first couple of pages they show a results of 473 Mbps over an
OC-12 circuit (a little less than line rate, but still quite good)
using Solaris.  Results with other operating systems varied.  I seem
to remember a presentation at the TCP Over Satellite IETF WG where
over 500 Mbps was reported.

My main point was that there is nothing wrong with the TCP
*protocol* that makes it under-perform at large delay*bandwidth
products.  The implementations are not necessarily up to the job in
some cases, but the protocol is sound.

(Further reference might be the TCPSAT WG's two RFCs: 2488 and 2760).

allman

---
Mark Allman -- BBN/NASA GRC -- http://roland.grc.nasa.gov/~mallman/