The first thing we need to do in order to allow free, unlimited incoming calls to our Asterisk server is to sign up for a free Ringback DID from SIPgate.com. Go ahead and register with them and you will get a confirmation email sent to you at the email address you enter during registration. This will provide you with a phone number we will setup with Google Voice as one of the phones it rings when someone calls your Google Voice phone number. Once you have activated your SIPgate account, log into it and click on Settings.
Here you will see your SIPgate DID phone number when you hover your mouse over your name. You will also need to click on the SIP Credentials to get your SIP user id and password for your SIPgate account.
Now we need to create a new SIP Trunk on our Asterisk Server. So under Setup, click Trunks and Add SIP Trunk. For the Trunk Name enter ‘Sipgate’ and for PEER Details, enter the following:
Before you submit these changes, enter the following for the Register String:
Don’t forget to Apply Config Changes and Continue. Now we will create a new Inbound Route for the SIPgate number. Under Setup, go to Inbound Routes. Enter ‘Sipgate’ as the Description and enter your 10-digit SIPgate phone number in the ‘DID #’ field. Under the ‘Set Destination’ section, choose the radio button next to Ring Groups and make sure ‘RingAll <700>’ is selected. This way calls to your Google Voice number will ring all of your extensions. Click Apply Config Changes and Continue. Now go ahead and call your 10-digit SIPgate phone number from your cell phone to make sure it does ring your phones!
Now we are finally ready to log into your Google Voice account and add your SIPgate 10-digit phone number as another phone on your account. When prompted, go ahead and do the confirmation drill to activate your SIPgate number within Google Voice.
We now need to log into our Asterisk Server via SSH (Putty) in order to run a script that will automatically add your Google Voice credentials into Asterisk. At the command prompt, enter the following commands:
chmod +x configure-gv
When prompted you will need to enter your 10-digit Google Voice phone number, your Gmail email account you use to log in to your Google Voice account, that password and then your 11-digit SIPgate DID phone number. It is important to enter the 11-digit version of your SIPgate number that includes a 1 in front of the area code.
Back in the web interface of your Asterisk Server, we need to tweak the settings of a newly created Inbound Route. So under Setup, click Inbound Routes and then click on the ‘gv-ringback’ route. Set the Description to ‘gv-ringback’, DID Number as your SIPgate 10-digit DID phone number, Caller ID number as your 10-digit Google Voice phone number and lastly, under Set Destination, choose Custom Destinations and make sure ‘Custom GV-Park’ is selected.
Congratulations!! You have successfully completed a fairly involved setup in order to be able to have completely free and unlimited phone calls to and from your Google Voice phone number using your traditional hand held home phones!