Why Your Workplace Wi-Fi Struggles

Understanding the roots of these wireless connectivity issues is an essential first step toward finding remedies.

Pouring tens of thousands of dollars into a Wi-Fi deployment does not guarantee magically outstanding results. We’ve all experienced office “dead zones,” areas in which connectivity falls suddenly, sometimes even to the point of disconnection. Alternatively, connections that work well one day might plummet the next—or vice versa. Obviously, lack of stable Wi-Fi performance can impair a workforce’s productivity.

Contention and Interference

In some ways, Wi-Fi clients and access points (APs) operate like walkie-talkies. Each participant must agree to use a common frequency and channel, and only one side can transmit at a time. With only two parties in an open environment, this approach works brilliantly. Unfortunately, such conditions rarely happen.

Run anyWi-Fi network scan and odds are that there will be at least a few detected SSIDs. If any of those networks is using the same channel as yours, then it will be competing with your network traffic. (Mind you, those are just the SSIDs you can see. Some don’t broadcast their SSIDs to keep them more secure, but the traffic is still there.) On a more granular level, the data packets flying between client and access point must “contend” with packets on competing networks.

If one of your packets collides with another network’s packet, your packet will fail to reach its target and have to be resent, which increases latency and slows throughput. Most access points can automatically change channels when confronted with excessive contention, but in today’s age of rampant wireless communications, it can be difficult to find a channel that doesn’t already have a fair bit of competing traffic. This is particularly true on the 2.4-GHz band, where there are only three effective non-overlapping channels (1, 6, and 11).

Similarly, Wi-Fi packets must battle against background RF interference. Cordless phones and microwave ovens are infamous for pouring noise into the 2.4 GHz band, which has the same effect on Wi-Fi packets as those from a competing network.

Most access points will respond to persistent interference by lowering their output power. This reduces the diameter of their effective range, hopefully removing the interference source from being within the AP’s sphere of communication. However, less power means lower transmission speeds, which leaves packets in the air longer...where they can collide with other networks and RF interferers. In reality, you want an AP that boosts power in the face of interference, not shrinks away from it.

William Van Winkle has been a full-time tech writer and author since 1998. He specializes in a wide range of coverage areas, including unified communications, virtualization, Cloud Computing, storage solutions and more. William lives in Hillsboro, Oregon with his wife and 2.4 kids, and—when not scrambling to meet article deadlines—he enjoys reading, travel, and writing fiction.