Hi!
The endpoints behind a VCS-C need to transparent talk to each other on a big variety of ports.
The concept of firewall traversal is a VCS-C+E.
You might get something to work with a ALG, just simple prot forwardind would not be enough.
Anyhow, this is not a supported solution so I would not go that way.
If you have multiple endpoints you want to look into getting a vcs-e or finding a provider which can
offer you that as a service could also be a solution.
"Jabber" is based on CUCM.
For JaberVideo, you would need either a VCS-E-Starterpack (that might anyhow be a option for you) or
TMS with the proper liceneses.
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