Allworx Technical Support Forum

I am trying to set up a remote Allworx phone. Both the remote phone and the Allworx system have private addresses behind routers. I have followed the procedure specified by Allworx running it in LAN Host mode with the router configured to do port forwarding on the Allworx system side. Everything works perfectly when I am using an Allworx 10x system running 7.1.11.1. When I try it with an Allworx 6x system running 7.4.12.5, the remote phone boots up fine, gets its configuration fine, but then displays "Registration Error!"

On the Allworx system side I had a Motorola cable modem/router connected to a Cisco 2811 router. Thinking that the Motorola cable modem/router was interfering with the SIP traffic, I replaced it with a plain Motorola cable modem (no router). I have the same symptoms. I confirmed that the Cisco configuration does not have any sip directives. The Cisco is running 12.4(25f).

I am at the end of my wits. Does anyone have any idea what the problem could be and how to remedy it?

Have you checked for any SIP ALG settings in both routers and disabled? In your scenario I think the remote router would be the important one.

Can you list all the ports you have opened?
Port 123 UDP isn't listed in Allworx documentation but is needed for date/time - shouldn't affect this problem though.

Are you using a domain name or IP for the Boot Server on the remote phone?

Do you have a static public IP that the Allworx is hosted on? Have you set that in the Network configuration? If it's in there, try taking it out. I recall having an issue like this early on, but don't recall the exact situation that caused it - I think it more had to do with using a domain name...

Thanks so much. After much Googling I finally found the solution.

It appears that my Cisco router fiddles with SIP packets by default and if you don't want it to you have to tell it not to.

Interestingly, the older Allworx software does not care if the SIP packets are modified but the newer Allworx software does care. I believe this is for security reasons to prevent spoofing.

I added the following line to the Cisco IOS configuration:

no ip nat service sip udp port 5060

Everything now works!