A few notes on monitoring VoIP performance in enterprise networks

I was recently asked about what products NetQoS has to perform the following functions:

  • Measure jitter, latency, QoS, and MOS (Mean Opinion Scores) for VoIP traffic

This isn’t a simple answer, but here is a summary I provided that may be useful.

There are different levels of VoIP monitoring…here are the main categories from my point of view:

  1. Monitoring the performance of the Unified Communications (UC) System itself (i.e. Communications Manager CPU, I/O, Call Handling, Gateway Performance, etc)
  2. Monitoring the performance of the network through simulated traffic (Cisco IP SLA does this directly in IOS but needs an external application to gather the statistics)
  3. Monitoring the performance of the network through analysis of the actual VoIP traffic.
  4. Traffic Analysis: Monitoring VoIP QoS Classification and bandwidth usage.

NetQoS can do all 4, but they require different products within the NetQoS suite.

NetQoS UC Monitor to do #1 and perhaps #3, and NetQoS NetVoyant to do #2.

NetFlow would be able to effectively monitor QoS classification and bandwidth usage (#4). NetQoS ReporterAnalyzer can do this, but NetVoyant will help.

I will expand upon these topics in the future – David