How WiFi speed is measured
When purchasing a business internet connection or network hardware (e.g., access points, security appliance), the price will include a specific data rate quoted in Mbps or Gbps. This refers to the amount of data that can be transmitted on your network per second. When an ISP quotes a 500 Mbps symmetrical connection, they’re telling you that you’ll be able to download and upload 500 megabits of data per second; if the connection is asymmetrical, download and upload speeds will differ with download typically being quicker. Similarly, an access point that advertises 1.6 Gbps is claiming that it’s theoretically possible for the network to enable 1.6 gigabits of data transfer per second. For reference, watching a YouTube video at 1080p HD uses ~5 Mbps. But, given the limitations of WiFi compared to wired internet connections, in both cases, your actual data rate will be much lower than what you’re quoted.Why WiFi is slower than wired
WiFi allows you to connect to a network wirelessly using radio waves. A client device (e.g., smartphone, laptop, etc.) sends data via radio waves to an access point, which connects to the broader internet and responds to your device via radio waves. Wired connections send data via electrical pulses over a physical cable. You can give any client device a direct internet connection by connecting it to a router via an ethernet cable. By transmitting data “through the air”, WiFi is more susceptible to failure. For example, the distance your device is from the nearest access point, the line of sight your device has to an access point, overlapping WiFi channels, dynamics of WiFi protocols, and device limitations all contribute to WiFi performance issues.Distance
As you roam farther from the access point your device is connected to, the signal strength of the radio waves used by WiFi degrades. Even if you place multiple access points around your space to always ensure a short distance to an access point, client devices prioritize maintaining a WiFi connection, so they tend to stick to the access point they’ve been communicating with rather than shift to the new nearest access point.Physical interference
Client devices need a clear line of sight to an access point to receive an adequate WiFi signal. This can be interrupted by physical interferences like glass, concrete, metal, and brick. Also, radio waves emitted by devices and access points can bounce off objects in your space, causing the signal to be received more than once and in a difficult-to-decipher format.
Competition from other devices
Since WiFi bands are a shared resource, only one device can communicate on a channel at any given time. Client devices must wait for the channel to be clear to send data, otherwise their data will collide. As a result, each client device only gets a portion of the bandwidth; for example, a 100 Mbps connection shared between five online devices means each device gets 20% of the bandwidth.The reality of speed tests
After understanding the reality of WiFi speeds, it’s important to note:- Network reliability must be taken into account along with WiFi speeds, and
- You likely don’t need WiFi speeds anywhere close to what you’re quoted.