Communications transmissions that don't price cash are usually stored off the CDR. Many Voice over Web Protocol (VoIP) providers supply free SIP-to-SIP calling. That is when a VoIP cellphone calls one other VoIP cellphone with out ever going by means of the general public change phone community (PSTN).
These calls will not be listed on the CDR, as a result of they are not billed. Nonetheless, calls made to landlines, cell phones, and worldwide numbers are all the time logged, as a result of they're charged on a per minute foundation.
Nonetheless, cloud cellphone techniques often supply methods to view the decision logs of Web calls that aren't billed. This information is usually discovered within the "name historical past" or "current calls" of your net cellphone service.