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Remote 7940 + CCM - one way RTP problem - NAT traversal ???

Hi all

We tried to connect remote IP Phone 7940 to CCM4.1(3). CCM has public Ip adress and 7940 is behind NAT (DEbian machine). Phone has registered normally, call is connected, but I have only one way RTP. RTP from IPT is going well, no RTP to IPT. I think, there is a problem in NAT. Is there a way how to travers NAT for RTP? When I am using IP communicator, solution is using my public IP address in item Preferences/audio/network. How to fix this issue with HW IP phone?

Many thanks for replies

Community Member

Re: Remote 7940 + CCM - one way RTP problem - NAT traversal ???

When the call is set up by call manager the CCM will use the IP Address the phone gives it for the RTP stream.

I am afraid you will have to either use a public address for the phone, or set up a site to site VPN

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