Path: utzoo!attcan!uunet!clyde.concordia.ca!news-server.csri.toronto.edu!utgpu!cunews!mentor.gandalf.ca!ddrg
From: ddrg@mentor.gandalf.ca (Duncan Glendinning)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Use of TCP/IP with satellite delays
Keywords: satellite
Message-ID: <1990Oct10.163646.3709@mentor.gandalf.ca>
Date: 10 Oct 90 16:36:46 GMT
References: <88084@aerospace.AERO.ORG>
Organization: Gandalf Data Ltd., Nepean, Ontario, Canada
Lines: 33

In article <88084@aerospace.AERO.ORG> obrien@aero.aero.org (Michael O'Brien) writes:
>Someone recently asked a question about use of TCP/IP over a satellite
>link, and since I've never worked in that realm, the ground got mushy
>under my feet.  I'd like a reality check.
>
>I seem to recall that TCP/IP is perfectly usable over a satellite link
>that has reasonably high bandwidth, but 300msec propagation delays.
>Adaptive retransmission and multi-packet frames get around this problem,
>no?  Of course, char-at-a-time telnet will lose no matter what, but
>mail and file transfers should move acceptably, right?
>
>More specifically I'm talking about something like a KA9Q implementation
>running via satellite radio link from a research vessel at sea.
>--
>Mike O'Brien
>obrien@aerospace.aero.org

We've successfully run SLIP over a satelite link between our offices
here in Ottawa, and both Wheeling IL, and Warrington UK.  Though a bit
slow for interactive use (9600 baud) it was possible.  The primary
use was for large (>1M byte) file transfers, where we saw better
throughput than kermit.  Here are some results:

   Wheeling IL to Ottawa Ont:
      file size: 2744320 bytes ftp: 76 min kermit: 995 min

Please note that the 9600 baud channel is just one of a number that
are stat muxed.
-- 
Duncan Glendinning         CAnet: ddrg@mentor.gandalf.ca, ddrg@gandalf.ca
Gandalf Data Ltd.          Voice: (613) 723-6500
Nepean, Ontario              Fax: (613) 226-1717
Canada  K2E 7M4