rjberke@berke.dseg.ti.com (Richard_Berke) (05/09/91)
This may not be the best board to post this query. Please forward if you know of a better one. I'm trying to collect information about the relative throughput reductions I may expect if I use satellite links instead of terrestrial copper or fiber. I'm aware of the approximately .6 second round trip time incurred per packet exchange, but I don't know how to assess this impact on real throughput. On domestic U.S. 56 K bits/sec leased lines, using MAC level bridges, I can achieve realistic 6 K bytes/sec reported throughput from FTP, using window=8192, segment=1025, mtu=1500 (ethernet on both ends). These for me have all been terrestrial copper and fiber, <= 1000 miles. I'm interested in what results I should expect for a 64 K bps link via satellite I'm planning internationally. I'm also interested in the effects I should expect if my long distance carriers' fiber fails, and they have to re-route my circuits over satellite. Does anyone out there have experience to share? Suggestions on tuning (TCP segment sizes, MTU, window, RTT)? I would expect many other folks have been wondering about this themselves, and may have studied the problem in depth already. Thanks, Richard Berke Texas Instruments richard@berke.dseg.ti.com PO Box 869305, MS 8428 /admd=mci/c=us/prmd=ti/pn=Richard.Berke Plano, TX 75086 214-575-2828 ------------------------------------------------------------------------------