Troubleshooting

Wi-Fi environments continuously change. Changes in performance are there for inevitable.

The solutions for problems that have rissen, are divers. It’s often easy to point out the root cause and the possible solutions. Troubleshooting is the proces that should lead to a solution to the problem. It’s the subject for the investigation. We always use a well defined investigation plan. Every problem is different and therefor needs a different approach. Problems are there, to be solved!

Spectrum analysis
Site survey (design)
Packet capture
Channel optimisation

Spectrumanalyse troubleshooting

Spectrum Analysis

Wi-Fi exists on the first two layers of the OSI model. Wi-Fi is also a very polite protocol. When it’s hears another Wi-Fi transmittion on the same channel? all other devices will silence. Is there another elektromagnetic energy source with a strength of -85dBm or stronger? all devices will silence.

Via a spectrum analysis we investigate the electro magnetic spectrum and solve the issues that we find there.

Spectrumanalyse troubleshooting

Site survey (design)

The state of a wireless network gets more visible by doing a site survey. Signal strength, channel usage, channel width, maximum theoretical speed etc.

A performance test to check whether the network (still) complies with the latest rules and regulations, is definately also a part of this task.

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Packet Capture

In some cases we see problems that are found in a higher OSI level. When we do a packet capture analysis, all data flows become visible on a specific channel.

This way we can discover for instance whether a driver (of a certain Wi-Fi device) could cause a problem or why a 4-way hand shake won’t work and logging on to a network fails.

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Channel Optimisation

Like Keith Parsons says: “A Wi-Fi signal consists of 3 things: “want – don’t want – don’t care“.

“We want a signal of -67dBm (want) but we don’t want any overlap on the same channel with a strenght of -85dBm or better (don’t want). A signal smaler than -85dBm, that’s no issue for us (don’t care).”

This is the foundation for a well designed chanel layout.