WiFi changed the way you connect to Internet. By allowing us to access the Internet through radio waves, the Wifi freed us from the wire. We use it to play games on the console, to watch Netflix on the TV and to look at photos on Instagram with the smartphone.
That being said, the speed of your WiFi depends on a multitude of factors, from the location of your routereven the microwave at home. Everything influences the performance of your WiFi, including the devices connected to your router. And here comes the biggest enemy: old devices.
Before understanding why an old device on your network can slow it down, it is essential that you look at WiFi and how it works. Simply put, your home WiFi uses radio waves to transmit data, and the signal must be strong for it to do so correctly.
To carry out this data transmission, WiFi uses a frequency of 2.4 GHz or 5 GHz. This frequency defines the number of waves that pass a fixed location in one second. Therefore, if you use 5GHz WiFi, a total of 5,000,000,000 waves reach your phone in one second.
To transmit data, the WiFi router changes these waves based on the data that needs to be sent. Consequently, if a one is being transmitted, a different waveform will be sent to your phone compared to a zero. To make these changes, Wi-Fi uses different protocols.
These protocols define different modulation techniques that lead to a difference in the amount of data that is transmitted over the WiFi. And it’s the 802.11b protocol that’s bugging your network.
Why an 802.11b device slows down your internet
Different protocols use different modulation techniques to transmit data. For this reason, a device using the 802.11b protocol cannot understand data transmitted by the 802.11n protocol.
That being said, WiFi has to be backwards compatible, and if an 802.11b device connects to a router that uses 802.11n, it has to work. Thereforeto solve this problem, the 802.11n router uses the 802.11b protocol to communicate with that device.
It is due to this reason your WiFi goes slow when old device is connected. That being said, the data rate does not change when the router connects to a modern 802.11n device, as it uses the newer, faster protocols.