Wireless Troubleshooting

Client Association Issues

• SSID
  • Check if they are trying to get to the right place
  • Each SSID can be associated with different VLANs, policies, performances.
• Authentication Type
• Key
  • Do they have the proper key?
  • Sometimes people just copies and pastes strings from an email.
• Signal Strength
  • Maybe the access point is oversubscribed.

Refraction

• A radio signal headed to a particular direction, encounters a wall/window, and gets through it but it affects its direction by a little bit
  • Different materials have different impacts on a radio signal

Reflection

• A radio signal headed to a particular direction, encounters a wall/window and bounces off of it.

Attenuation

• Signal loss
• We send a signal and it is fantastic right next to the access point
• When we start getting far away it starts losing strength, maybe the audio is begin cut down.
• They can sniff wifi from space, but there are scenarios that you may not have a signal to run beyond 10 ft, because of refraction and reflection.

Interference

• Frequencies intercept/overlap with each other.
• More modern modems look at the airspace and automatically deduce their channel.

Wireless Heatmap

• A drawing of your floorplan with the access points indicated.
• A map taht shows you the strength and weaknesses of your wireless signal.

Spectrum Analyzer

• Look for sources of noise.

Traffic Stats

• doing a netstat -e from your command line
• You can look at the number of discards and errors and deduce more or less what is going on with your network.