Controlling packet loss and jitter is essential if an adequate quality of service is to be maintained. Traffic Sentinel makes use sFlow® to obtain packet loss and jitter measurements from switches and routers throughout the network.

The following pair of charts trend packet loss rates and jitter:

While the packet loss chart shows fairly consistent performance, there is a clear spike in jitter at 10:35. The following chart shows jitter broken out by zone and clearly shows that the problem is confined to the Embarcadero zone:

Traffic Sentinel's ability to directly monitor quality of service metrics provides a useful assurance that quality of service goals are being met. However, monitoring quality of service metrics alone doesn't provide the early warning needed to avoid noticeable degradation in service (see Managing Quality of Service Using sFlow). The rest of this example will demonstrate how Traffic Sentinel can be used to proactively manage the network and avoid quality of service problems.