Redundancy increases the chance of alarms getting through.
Your detector is redundant if it alarms over different connections. For example, over GSM and PSTN (simulated analogue line). The form in which systems are redundant varies considerably and that influences the reliability just as much.
Read more about redundancy in alarms.
With the Octalarm-Touch and the Octalarm-Touch Pro we also recommend installing the free app Adésys Alarm on your smartphone. In the dialler you can select an alarm as 'critical'. With a critical alarm, the dialler sends a message via the app even when your phone is on night or flight mode, so you can be sure that a critical alarm will be received (push-alert).