How to configure the Cisco 7940G IP Phone for Standalone SIP? It’s a common problem while using the Cisco ip phone 7900 series. Now here we will share an example and case that the user of Cisco 7940g phone has got…
And the discussion is likes this:
The Problem: “I have a Cisco 7940g IP telephone.
I do not have a PBX. This is simply an IP phone plugged into a my LAN.
I just signed up Digium cloud SIP service.
Is there a way to make this work?
P.S. I tried entering the credentials that Digium sent me into the "5. SIP Configuration" menu under "SETTINGS" on the phone, but I still have an 'X' over my line on the home screen.”
Someone answered: “Digium is a very-well known company because of a VoIP product called Asterisk.
Will the phone work, of course? You have a choice of running SIP or Cisco-proprietary SCCP.
We'll need to do a top-to-bottom troubleshooting and configuration. Firstly, what protocol are you planning to use (SIP or SCCP) and what configuration settings does Digium require you to do from your side?”
In fact the user wants to run SIP. He does not have any PBX or other Cisco phone hardware outside of this 7940g phone sitting on desk.
He has factory-reset the phone, and entered the credentials Digium gave him.
Settings > 4. SIP Configuration > 1. Line 1 Settings:
1. Name = (the user’s assigned Digium phone number)
2. Shortname= (his name)
3. Authentication Name=56605ed547a8437d872f6b516df6a4bc
4. Authentication Password = (another random string of characters just like the previous field)
5. Display Name = UNPROVISIONED
6. Proxy Address = sip.digiumcloud.com
7. Proxy Port = 5060
And he have confirmed with our sysadmin that the network's router is set to (1) disable "SIP helper", and (2) allow communication on specific UDP port ranges, both per Digium's knowledgebase.
…Those configuration are not enough.
Ask Digium if NAT & ALG are supported.
What transport protocol does Digium support: TCP or UDP
What codec is allowed?
The Cisco IP Phone 79X5 family of phones behave differently. It's not like the IP Phone 79X0 where the configurations are simple. You'll need to upload the complete set of configurations to the phone using DHCP Option 150 and a TFTP server.
…Any more suggestions? Share with us…