With so many different types of wireless devices out there today, you’re probably experiencing radio frequency (RF) interference in your wireless network whether you know it or not. RF interference is ubiquitous and there is no way to completely avoid it; the best you can do is identify sources of interference and take them into account when designing your network.  Meraki has introduced a new tool in Dashboard to determine whether interference is affecting your network adversely and to help you optimize your network for the local RF environment.

In the Meraki Dashboard, go to the access points list under the Monitor tab, and click on any active access point.  The channel utilization graph shows the percentage of time the access point has seen RF interference on its channel.  For example, if the access point is operating on channel 1 in the 2.4 GHz band, then the graph will show the amount of time channel 1 has seen interfering RF energy.

The percentage of utilization on the channel proportionally affects the peak performance that access points will be able to achieve.  Percentages higher than 30% can cause considerable connectivity issues. Here are some suggestions for reducing or coping with high levels of interference:

1.  Perform an RF site survey before deploying your network.  You can use the Real-Time Spectrum Analysis tool found on the Client Survey Tool tab of with a battery-powered access point or a 3rd party spectrum analyzer to get an overview of the RF environment in your chosen place of deployment before installing your APs.
2.  Remove interfering devices from the area.  Common culprits are 2.4 GHz cordless phones, Bluetooth gadgets, microwaves and wireless video cameras.  A 3rd party packet sniffing tool can be very helpful to identify and locate interference sources.
3.  Ensure adequate wireless coverage to avoid weak spots; a weak signal from your access points is more easily degraded by local RF interference compared to a strong signal.
4.  Avoid using the same channel as neighboring wireless networks.
5.  Turn on channel spreading in Dashboard (go to the Configure tab and click on Network-wide settings) so access points can individually pick their own channel based on the RF interference they detect.
6.  If you are using Meraki 802.11n hardware, consider using the 5 GHz band to avoid the often congested 2.4 GHz band.

Using this new tool and following these simple tips will help you minimize RF interference effects in your Meraki network and optimize performance.

-Posted by Ahmed Akhtar