Issues trying to connect Cisco TelePresence SX20 to another Video Conference Unit

[joeyo89]

HI Guys,

We have been having issues trying to get our Cisco TelePresence SX20 to connect to another video conference unit outside of our firewall. We have gotten audio but no video when connecting to a test site and this random "100" number calls come in every 2 minutes.

Our Firewall:
-smoothwall
-allowed ALL ports in and out to the private IP
-smoothwall support has looked at the data going in and out when we connected to a test site. But with the test site we only got audio and no video, but there were packets going back and fourth.
- Port forward from the public IP to the private IP

Is there anything else you can tell us to help us out?

 

[bill001g]

In most cases the firewall needs a special feature to make nat work. Many of these systems use h323 to sip to set the calls up. The problem is they then use UDP ports that also need nat/port forwarding to work. Many firewalls are generally setup to read the call setup messages and dynamically put the the rules needed in to make the UDP pass though correctly. You need to read the manuals for the firewalls and see what things they support...the exact name fore this feature is not standard but there is usually a discussion of SIP and NAT in devices that have support.

If this is the same system that cisco bought from tandberg years ago it has another protocol for setting up video calls that most firewall don't know about. I have not seen after cisco got them but there were very special options you had to set to force it to always use a certain block of UDP ports and you had to forward them in the firewalls manually.

I would have hoped by now the were using SIP but these are strange boxes in that they form many-many sessions which is very different than any form of point to point video setup.

My knowledge on these devices is very outdated so this may not apply anymore.

If you can run them over a private vpn they tend to be pretty easy to setup.