QoS Alerters are a basic feature in the OMCR, they shall all be activated in order to provide additional supervision on the cells (= Basic Alerters)
Without them, some problems (such a GSM / GPRS sleeping cells, high call drop, etc) cannot be detected because there are no alarms !
You can even create additional alerters (called “QOS Alerters”), which you can configure to be triggered by a certain indicator, above a certain threshold. It is extremely interesting if the only supervision of the network is done on the OMCR. If you have a dedicated 24/7 team on the RNO also, then it is not mandatory to activate alerters.