We have a client using a UC320 with SIP VOIP. They have a range of phone numbers. Most begin with 1207xxxxxxx, with another that is 1800xxxxxxx. We have to enable the 'only calls to' box, otherwise they get spam calls with CID of 1000 or similar.
Here's the problem. If nothing is set in the box, they get spam calls, but the 800 number functions. If we put 1207xxxxxx in the box it kills the 800 number. In the number routing from our VOIP provider I have set the 800 number to be translated as their main 1207 number. I spoke with the provider and they did some investigation. They are sending the CID as 1207xxxxxxx, but apparently not in the right place in the SIP header. They are able to change it to match the UC, they just need to know where the router pulls the info from.
What part of the SIP header does the UC320 use to determine what the incoming CID is?
