[isalist] Re: Question regarding video conferencing

Odds are good that you're hitting TMG connection limits with these clients.
The more they interact, the more traffic and connections they create.
Do you see any connection limit alerts from that time frame?

Where did you get those ports/protocols?
I tried searching the Vidyo site and while it's very pretty and all 
SilverLight-y, it's a major PITA to find anything more than marketing spew.

It's also entirely possible that you simply can't use this application across a 
truly stateful firewall such as TMG.


From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On 
Behalf Of Rob Moore
Sent: Wednesday, January 18, 2012 9:21 AM
To: isalist@xxxxxxxxxxxxx
Subject: [isalist] Question regarding video conferencing

Hello-

We have our own video conferencing solution, from a company called Vidyo. The 
simplest solution was to put the hardware outside our TMG firewall. (We have a 
group that manages the Vidyo portal for us and they say it's fine to have it 
out there.) I have allowed a variety of traffic to it, including: HTTP 10000, 
17990, 17992, 3306, 50000, and UDP 50000 - 65535.

We are having some rather quirky issues with it and have done a lot of testing 
to try isolate exactly where the problems lie. What happens is, we get people 
to connect to our portal. Everything works normally for everyone. Then, maybe 
10 minutes into the conference, bad things start happening. Audio starts 
breaking up. Video gets jerky. The number of people you can see in the meeting 
drops to only two or three instead of staying steady at six or eight. (This is 
a feature of the Vidyo software. If you have poor bandwidth, Vidyo only shows 
you the person speaking and maybe the last speaker or two. But we don't have 
poor bandwidth. We have a 100Gb connection to the Internet.) The weird thing is 
that these bad things don't happen to everyone. They don't happen to people 
connecting to the portal from outside the network. And they only happen to some 
of the people connected inside the network. We've had as many as eight 
simultaneous connections, and some will be working fine showing eight 
participants, while others will be having trouble and only showing two or 
three, with audio and/or video problems. I've looked to see if it could be a 
switch problem, but some of us without problems are connected to the same 
switches as those with problems.

We've also tried connecting to a remote Vidyo portal. The remote users had no 
issues, but we who were connecting through our TMG server did have problems.

It seems like the most likely culprit is TMG, although the data don't fully 
support this conclusion. It seems to me if TMG were at fault, all users would 
experience the same problems at the same time. But that's not the case.

Since the problems don't start until something like 10 minutes into the 
conference, it's as if something were throttling the traffic at least for some 
of the computers. As far as I know, nothing like that is going on. In the past 
I've looked to see if I can see any problems by monitoring traffic on TMG, but 
never found anything. It's been a while since I've done that, though. So it 
might be worth looking again.

Any ideas about what might be going on, or suggestions to pursue?

Thanks,
Rob

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Rob Moore
Network Manager
215-241-7870
Helpdesk: 800-500-AFSC

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