Port forwarding for external SIP softphone

[acejavelin]

I am very familiar with the proper ports to forward for an external MiNet or Inter-Tel phone on the 5000, but what ports need to be forwarded for a SIP softphone to work from the public internet, specifically the Bria softphone client? I know 5060 but are any other ports required, say for RTP or other messaging?

[Tech Electronics]

Acejavelin,

When dealing with SIP the only port needed is 5060. Make sure the customer doesn't have some sort of SIP inspection turned on. Also don't forget the 5000 actually does a SIP/SDP mismatch within its message so if the Layer 3 does make a change it will most likely put in the LAN IP Address when sending it to the softphone.

Thanks,

TE

[acejavelin]

Hmm... they have a Sonicwall and my experience with those has been, well, lets just say "less than ideal" for many VoIP applications. And the IT vendor seems a bit less than knowledgeable about it. Guess I will just play with it and figure it out. Thanks.

[Tech Electronics]

AceJavelin,

Sonicwall has a feature called SIP Transformations, what others call SIP-ALG. I am not sure as to why this feature was every created as it has never worked on any installation I have been on, but, make sure this is turned off so that it doesn't change your SIP packets.

--Update--
Here are some notes I have on Sonicwall devices.

Get the latest firmware, there are SIP bugs in lower versions that cause "odd" problems.

Uncheck Box - “Use SIP Header Transformation” or “Enable SIP Transformations”
Check Box – Enable Consistent NAT

Additionally, when you set the Global Default UDP timeout value on a SonicWALL firewall, you still MUST fix the pre-existing rules’ individual UDP timeout values. New rules will inherit the Global Default. Since 30 seconds is no longer a sufficient UDP timeout as it once was (to allow for the UDP heartbeat sessions to keep-alive from the phones to the border manager), we must increase the UDP timeout to the suggested 300 seconds Globally on the firewall, AND the specific out-bound firewall rule (or default rule as the case maybe) to the UDP timeout of 300 seconds.

Thanks,

TE

[acejavelin]

Awesome! Thanks for the info... I will forward this on to the customers IT person, since the softphone works in house, but from the public internet it registers but no audio is passed.

[acejavelin]

FWIW, if anyone is interested...

Nothing we did with the Sonicwall router would allow the Bria SIP phone to pass audio... Put in an Asus RT-N66U with a separate public IP and made it the default gateway for the voice VLan and updated the 5000's IP settings, and everything was up within 15 seconds of changing IP in softphone. Only change to Asus out of box was static WAN IP and port forward 5060.

These Asus routers, especially mated with RMerlin firmware, never cease to impress me. I highly recommend them, especially for sites you want to do remote maintenance on that have dynamic public IP address since they have a free DDNS client built in.