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HELP!!! 7940 IP phone with SIP


Let me start by saying that I love this community, I've learned a lot from this community. I have a 7940 IP phone that a friend changed to SIP protocol. I'm wanting to use it as a business phone. A friend told me I could get free service using Ipkall,, and google voice. Anyone know how to do this? I would like to make outgoing calls as well as receiving incoming calls. Free is fine but willing to pay a reasonable monthly fee for a single service that can simplify this. Phone plugs into a Cisco 3524 switch, using a 2821 router W/Charter broadband. Any expertise will be appreciated


HELP!!! 7940 IP phone with SIP

Hello Willie,

I think cisco 3524 is an inline power switch , so you don't need any POE to get power for 7940.

First you need to configure your 2821 router as a CUCME(call manager express) and get you 7940 registered with it.

Here is the link for basic configuration on your router to support CUCME -

Once you get your phone registered with CUCME router , then you need to configure dial-peer on router to get call routed to sip provider. Here is a good video to get setup sip account on google voice and CUCME router.

If you get some problem in CME setup , let us know we will help you.



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Re: HELP!!! 7940 IP phone with SIP

You should have valid credential to use this sip domain plus additional parameters like port, codec, media.

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