While tools like Cisco Prime and Aruba AirWave do a great job of monitoring and producing lots of alerts, how do you monitor the network from a perspective

We’ve seen a lot of bugs over the years, which affect the end devices and ultimately the user experience.

A typical example, would be where a device roaming from one AP to the next fails to roam correctly. In the case of a WiFi phone, this typically results in a period of silence, which is pretty annoying for the users. With this particular bug, the phone was able to roam and connect, but the AP failed to send any of the end user traffic to the phone.

Taking this scenario, and understanding that this is a bug, the alerting on the network is unlikely to pick it up. While you’ll get lots of alarms for an AP failing, or a controller going offline, alerting on the state of the user connection is a different matter.

There’s a number of built in tools, which might help proceedings and some new ones which could too. Let’s take the existing tools first.

Cisco has Traffic Stream Metrics (or TSM to give it the snappier acronym), which collates data for the state of play for a voice call. As a phone moves around, it has to roam frequently, and for short (very short) periods it is offline, while it is authenticated onto the new AP (typically in the order of milliseconds). Coupled with measuring the state of the coverage (good signal, good SNR and so on), TSM can give you a good indication of the state of the network and the user experience. It’s not the be all and end all though.

Cisco Prime does a good job of producing graphs for clients – you can see the historic roams that have taken place, the average SNR and RSSI on a graph – all good stuff for basic connectivity.

But let’s return to the subject of how to monitor from the client’s perspective? Aruba has a new feature on the market, for just such an issue. It’s called Aruba Clarity and allows an adjacent AP to become a client for a short period of time. In this mode, the AP will connect to an adjacent AP as if it were a client – it flips to client mode, connects, confirms all is well and drops back to normal AP mode.