Cellular monitoring with ADT is primarily done using the AT&T cellular network using CDMA technology.

Does ADT work off cellular?

Even if you don’t have a home phone, you can still take advantage of ADT monitoring with CellGuard. CellGuard uses cellular technology instead of a landline to communicate with the ADT monitoring center. Some VoIP and digital phone services also connect to the ADT monitoring center.

What is cellular failure on ADT?

A GSM Fail to Communicate indicates that the alarm panel has tried to send a signal to the Security Monitoring Centre via the Mobile phone network and was unable to send the signal.