Re: Round-trip delays

Brian Godette (bgodette@idcomm.com)
Wed, 24 Sep 1997 15:24:50 -0600


At 05:59 PM 9/24/97 +0930, you wrote:
>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.
>
:) Not the worst I've ever seen for CU chat... worst I've seen is a round
trip of 15 MINUTES. That was in the "old" days (95) on NyserNet2 and the
person this lag was happening to be in NY (state) as well.

Anyways, was the 60 second lag for CU chat or PowWow? If it was for CU, if
you're connected to a ref, doing a traceroute/ping from your system to the
other client is irrelevent, you would both have to do traceroutes/pings to
the reflector and add the averages together. As for PowWow, it's my
understanding that chat sessions can either be group based or direct (ala
IRC & /DCC chat), the same thing would apply here, that unless the
connection is direct point-to-point, you have to ping the central server
from both sides.