I have a few vigor 2800 routers in the field and am having NAT problems.

Below is an except from the NAT table off one of the routers showing 2 IP phones connecting out -

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Private IP :Port #Pseudo Port Peer IP :Port Ifno Status

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192.168.1.11 5060 5060 217.196.0.131 5060 3 0
192.168.1.10 5061 5061 217.196.0.131 5060 3 0

As you can see the router is using the private src port as the psuedo port, rather than assigning a unique pseudo port to each connection. Maybe I have a limited understanding of NAT but this seems to completely break NAT functionality. In this case I have managed to fix the issue by setting both phones to use a different src port. To begin with, both were using 5060, and obviously the router was unable to correctly deliver return packets to the correct device.

I now have the same problem with a 2nd site but the customer is using cisco phones and I can see no way of changing the src port.

I have a vigor 2910 in my office here, and it is functioning fine with over a dozen IP phones. The NAT table shows that all the phones have been assigned unique pseudo ports above 45000.

Has anyone else had this problem or found a solution? The router I provided the table from above is running firmware 2.8.2 which I believe is the latest version.