SX20 registered to a Polycom network, can only call other registered Cisco endpoints on the same network

[KBLAIR1]

Hello all,

I'll preface my question by first stating that I've been running our videoconferencing network for about 3 years now, and the depth of my knowledge unfortunately is strictly self-taught. I work in a hospital with 10 subordinate branch clinics scattered across 5 states. Up until about a month ago, our network was purely Polycom equipment. We had a new clinic open a few weeks back, and included in the builder's contract were 3 conference rooms built out using Cisco endpoints (SX20, for reference).

I was able to register all 3 endpoints to our gatekeeper, Polycom DMA 7000, with no issues. Where I'm banging my head into the wall is why I can't connect any calls from either of those 3 endpoints to any endpoints here in the main hospital or to our bridge. The call logs on the gatekeeper state no media path available and tears the call down. IF HOWEVER, I call one of the other Cisco endpoints in that same building, the gatekeeper has no issues completing the handshaking between the two endpoints and the call is connected successfully.

Has anyone ran into this issue by chance before?

[Wayne DeNardi]

If calls within the building are working, but calls across your WAN are not, then I'd be looking at any firewall present between the building and the rest of the WAN and checking that all the required ports are open between the endpoint and your Polycom infrastucture.  It sounds like the basic call signalling ports are open, but the media ports are being blocked.