Alan,
The ISP could be employing some type of packet shaping that is queuing your
various data streams. At least, i've had this happen at my university in the
past and it manifested itself with my outgoing video and audio streams
arriving at various times (generally intact, but sometimes slowed down or
sped up as things caught up after being queued). My first stream had
priority, but the rest did not.
You can see the ports associated with the audio and video when you pull down
the properties command under... i think it's under the file menu on the venue
client. That may help if you can then look at the traffic associated with
that port/ip.
I'm also assuming you were bridging (unicast) as well. In general, the audio
and video seem to be in sync simply due to network speeds and bandwidth on
I2/etc. I believe. Also, your uplink bandwidth on your DSL is probably much
lower than your downlink bandwidth causing some congestion on your outgoing.
Were you exceeding your available bandwidth? Which way were you seeing the
delays? Changing the location "room" wouldn't change anything except the
ports you're sending/receiving on so I'd actually be surprised if it changed
then. If you changed venue servers (went to NCSA instead) and saw a
difference (like it went away) then that would be interesting to note. If i
use my ADSL connection I have to VPN to my campus first out of my ADSL in
order to get the ports i need in/out and through the nat'ing etc. And then a
session could easily blow away my available (even my 6Mb downlink) bandwidth
on the incoming not to mention there is no QoS if i'm not VPN'd.
Just some thoughts from what little i know... John Q.
--
John I. Quebedeaux, Jr.; Louisiana State University
Computer Manager LBRN; 131 Life Sciences Bldg.
e-mail: johnq@xxxxxxx; web: http://lbrn.lsu.edu
phone: 225-578-0062 / fax: 225-578-2597
On Sep 29, 2006, at 7:11 PM, Alan Sondheim wrote:
I've been working on a PIG in Brooklyn, New York, through DSL, connected
through Argonne to an AG at West Virginia University, Morgantown. We're
using 2.4. My question - the sound delays approximately 7.5 seconds (the
video is about .5 which is understandable). What could cause such a large
delay? I don't think it's congestion; we tried the Lobby as well as the
Test Room; the results were the same. One reason I'm curious - I work at
times in sound and it would help to understand the mechanism here.
Thanks, Alan, sondheim@xxxxxxxxx
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