In an alarm storm, when hundreds of thousands of messages may be flying in, NFM cuts to the chase, suppressing those not related to the root cause. The result is network-wide analysis that sorts through a flood of alarms from many EMSs to detect the root cause, whether it's in a link from Dallas to Denver or a media gateway in Manila. NFM also gives network managers extra help in focusing on top-priority alarms. NFM can override the normal stream of data displayed on the NOC workstation screen to focus only on an urgent alarm. The network gets pretty noisy over a cable cut or other system failure.
Black holes emit no alarms.
The only evidence of their presence is the messages that simply aren't there. It can trace holes to specific parts of the network and even individual facilities or pieces of equipment. Then, once you know you're looking for a problem in a specific system, you can use NFM to analyze data coming from the system to diagnose the trouble. For example, if you see calls failing amid a storm of alarm messages, you know it's a system or physical problem like a cable cut. If you have calls failing, but all you see is an absence of messages about them, you know you've got a software glitch like a translation table error.