by admin » Tue Mar 02, 2010 8:18 am
Could you PM me your number and I'll have a look into it, the server itself sends out CNAM (if available) and CID, it is whether or not the different carriers your call is routed through blocks our CID/CNAM.
Caller ID works like this; if John Smith calls Jane Smith, his telecom may only pass CID (number) so the receiving phone company searches a CNAM database (ie if Johns number is 519-555-5545 it would most likely show 519-555-5545 - Known As John Smith) for John Smith's CNAM. Whenever a Caller Name Identifier is pulled from that database, it's called a CNAM Dip. Each time we, or any other telco does a "CNAM Dip", the originating telco is compensated; what happens when we trunk on CID/CNAM and it does NOT get pass through is obvious to you now, since it is blocked, your callee's telco thinks we aren't passing CNAM, when you call someone that is subscribed to CNAM based CallerID, the caller name in such cases often shows up as "out of region" or "unknown".
So really; if we pass CNAM and CID, and the CNAM is blocked somewhere along the route, your number may come up as anonymous or Unknown, because that provider, or that specific customer is looking for CNAM only, not CID.