Round-trip delays

John Ingham (johningh@tafe.sa.edu.au)
Wed, 24 Sep 1997 17:59:23 +0930


Hi all seekers,

The other day I was using CU-SeeMe and PowWow to talk with a friend in the
USA from Australia. We experienced a "round-trip" delay of some 60 seconds
- yes that's right, it took 60 seconds for an answer to arrive to a
question!

When I used "Tracert" to check out the path between him and me there were
about 15 hops, each varying between 150 msec to 1500 msec, but adding up to
no more than 6 seconds total delay.

Why would this measured time be so much smaller than the actual delay
experienced by using CU-SeeMe (Chat and Video) and PowWow (Chat and Sound)?
Are "Ping-type" packets handled by servers more quickly than packets
containing real data? Thankyou.

John Ingham
Supervisor, Technical Operations, TLC (Tele-Learning Consortium)
Adelaide Institute of TAFE (Training and Further Education)
GPO Box 1872 Adelaide South Australia 5001
Ph: +61 8 8207 8550 Fax: +61 8 8207 8552
Email: johningh@tafe.sa.edu.au
Web Site: http://www.tafe.sa.edu.au/video-conf/
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