Also sprach Tim Devries

I think this question may have been asked before, but what is the minimum latency and delay I can expect from a satellite connection? What kind of delay have others seen in a working situation? What factors should be considered in end to end connectivity architecture when utilizing a satellite link?

Well, as a lower bound, geosynchrous orbit is between 22,000 and 23,000 miles and the speed of light is approximately 186,000 miles per second. The math is not terribly complex from there. Figure up and back is around 45,000 miles, then if you're doing a round-trip, you're up to around 90,000 miles...that's on the order of a half second right there. That's why I laugh when BellSouth tries to tell the Kentucky PSC that satellite is a competitor to DSL...ever tried to type over a 1/2 second lag on telnet or ssh? Painful doesn't adequately describe it. -- Jeff McAdams Email: jeffm@iglou.com Head Network Administrator Voice: (502) 966-3848 IgLou Internet Services (800) 436-4456

Speaking of Starband.. I have seen latency in the 1.2 second range. This was over a year ago so maybe they have gotten better.. Michael... On Tue, 26 Feb 2002, Roy wrote:

One of our customers tried Starband. Ping time from our mail server to his was normally 800-900 ms.

Tim Devries wrote:

...

Hello,

I think this question may have been asked before, but what is the minimum latency and delay I can expect from a satellite connection? What kind of delay have others seen in a working situation? What factors should be considered in end to end connectivity architecture when utilizing a satellite link?

Any help appreciated,

Tim

On Tue, 26 Feb 2002, Barb Dijker wrote:

I have a tachyon.net system. 600ms is typical with a good aim.

They use particularly slow tachyons :) --vadim

DirecPC (Hughes) now has a business grade service called DirecWay. Haven't tried it. One would expect it would be better than the ones intended for residential only. It claims to go to 1.5M down like Tachyon.

I use Direcway presently as my primary link. I refer to it as, "Dialup Plus!" As a previous poster noted, ssh sessions are painful. I now resort to typing e-mails out in a local text editor and cutting and pasting them into my ssh window. Here's a local traceroute performed just now at 7am on a Wednesday to a random service like Google. Performance gets significantly poorer during peak business hours. High d/l rates are only achievable late at night it seems. 1 797 ms 810 ms 810 ms 172.23.4.17 2 742 ms 686 ms 742 ms 172.23.4.17 3 796 ms 755 ms 742 ms 172.23.128.2 4 920 ms 755 ms 742 ms 192.168.11.251 5 741 ms 755 ms 687 ms 63.215.128.137] 6 742 ms 741 ms 687 ms [64.159.18.6] 7 755 ms 741 ms 742 ms 209.249.0.173 8 796 ms 742 ms 755 ms [209.249.0.213] 9 742 ms 755 ms 741 ms [208.185.0.137] 10 783 ms 810 ms 824 ms [216.200.127.26] 11 810 ms 879 ms 810 ms [208.184.233.50] 12 810 ms 811 ms 810 ms [208.185.75.198] 13 742 ms 810 ms 810 ms [216.239.47.18] 14 811 ms 810 ms 810 ms [216.239.47.162] 15 783 ms 796 ms 824 ms www.google.com [216.239.35.101] /david