atcomsystems.ca/forum Forums TDM Business Telephone Systems Inter-Tel Telephones & Systems 8622 VOIP/NAT Question

Hello All,
Did some searching on here and found a lot of helpful info! Unfortunately, we are still having some issues with no voice going out from the IP phone.

After checking my firewall's logs I found that the IP phone seems like it is trying to use the IPRC's internal NAT'ed address.

[New UDP Outbound Flow] (UDP) LAN to WAN 192.168.111.60:5006->192.168.1.40:6226 [Forward]

I spoke with the company that installed the phones/5000 and they said that everything should of been set correctly. Does this seem right though that the phone is trying to find the IPRC's NAT address and not it's public?

Thanks in advance!

there is a setting for each endpoint that defines how it will handle NAT traversal. The settings are:
Native: The endpoint will communicate with the IT5K on it's inside non NATd IP
NAT: The endpoint will communicate with the IT5K on it's NATd IP (External IP)
Auto: The system will auto detect if the endpoint is external to the subnet.
I would use the Auto setting.
I am assuming that the endpoints are connecting from the Public Internet.

Hi Chris,
Thanks for the reply.

I am not sure what the company that set up the phone system configured for the endpoint communication. But it does sound like it is set to Native. Is this setting on the phone or something that has to be done through the 5000?

It is in the 5000 under System/Devices and Feature Codes/Endpoints/IP Settings/NAT Address Type
The config is in the 5000 because it communicates dynamic port information within the payload of the packets to the endpoint which also includes source IP address. It modifies these packets based upon this setting.

I am having the same issue as the OP, we can receive calls on the IP phone and they can hear the other caller, however the auto from the IP phone will not go out.

Check your NAT settings in the system and check your Firewall ACLs.

I have all of the ports open that I was told to open and have read about. Inter-tel has been contacted but they weren't much help.

We even tried allowing all ports open to go to the Card and it still wont allow the incoming voice.

Ok, well if you opened it wide then the issue is definitely in the 5000 config. You need to make sure that the NAT IP is defined under IP connections and make sure that the endpoint is flagged for either NAT or Auto. That will fix your problem.