I'm pretty much an amateur at this; when I went to the Test Room the main thing I noticed was a much clearer audio signal - the delay seemed about the same. I measured the delay back and forth from Brooklyn to WVU in a couple of ways - by comparing video and audio signals (Jimmie at the other end would speak and wave something - I could tell the delay between the two), as well as using our cellphones. The difference was palpable.
- Alan On Sun, 1 Oct 2006, John I Quebedeaux Jr wrote: > 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: [email protected]; 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, [email protected] >> >> blog at http://nikuko.blogspot.com - for URLs, DVDs, CDs, books/etc. see >> http://www.asondheim.org/advert.txt - contact [email protected], - >> general directory of work: http://www.asondheim.org >> Trace at: http://tracearchive.ntu.ac.uk - search "Alan Sondheim" >> http://clc.as.wvu.edu:8080/clc/Members/sondheim >> >> > blog at http://nikuko.blogspot.com - for URLs, DVDs, CDs, books/etc. see http://www.asondheim.org/advert.txt - contact [email protected], - general directory of work: http://www.asondheim.org Trace at: http://tracearchive.ntu.ac.uk - search "Alan Sondheim" http://clc.as.wvu.edu:8080/clc/Members/sondheim
