RMX2000 External IP Calls

Occasional Contributor

RMX2000 External IP Calls



I was hoping somebody may be able to provide some assistance.


I am wishing to configure our RMX2000 to accept IP calls from external parties.


The RMX is running version firmware and the IP Network Service has Fixed Ports selected (TCP 49152 - 50500 UDP 49152 - 50175). The external IP is MIP'd to the signaling host IP with H323, HTTP, & HTTPS permitted on the Juniper Firewall.


When using M100 to test on a PC connected to a residential broadband connection I am able to start a call, but I have no sound or picture. When I call a HDX 6000 end point by it's MIP'd external IP I can connect without any troubles.


Looking from the RMX I can see the call enter the Entry Queue.


I have seen some posts refer to a VBP and I am starting to wonder is this necessary before it will start working??

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Polycom Employee

Re: RMX2000 External IP Calls



The VBP is an ALG that we sell for the purpose of firewall traversal and WAN to LAN NAT in a video environment. The reason your calls are failing is that the RMX uses a minimum of two different IPs to set up a video call. The signalling IP is where the H225 traffic is sent to set up the call, but once the call is up, the media goes directly to the address of the media card. That address is returned to your M100 in the application layer, and the bridge is going to put its LAN address in there, which will not be routable.


Unless your NAT is an ALG (that is, it nats layer 7 as well as layer 3) then it will not work as the address in the application layer of the packet will give the endpoint an unroutable address. The VBP solves this problem by putting its own WAN address in layer 7 of all the packets, but preserving the LAN side destination address to get them back to where they belong on the LAN side.

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