Bridges vs Wi-Fi

Bridges VS Wi-Fi

Some devices connect to HomeKit using Bluetooth, some over Wi-Fi, some over Thread, and some use Bridges. They all have pros and cons. Often times, people will ask what is better, a light that connects using a bridge, or a light that connects directly to Wi-Fi?

Several popular HomeKit devices connect to HomeKit using Bridges, such as Lutron Caseta, Hue, and Aqara.

Note: Some people incorrectly call HomeKit Bridges "hubs". This is partly because manufacturers often times call them hubs because when used by themselves outside of HomeKit they are hubs, but a HomeKit Hub is something else entirely. A HomeKit Bridge "bridges" a manufacturer's proprietary ecosystem into HomeKit. It is usually a small box about the size of an TV that plugs into your router via Ethernet.

Many people will tell you they don't want to buy devices that require a bridge. That is not good advice, in fact, I consider it the worst possible advice a person can give you about HomeKit, and is usually coming from somebody who had a bad experience and doesn't fully understand what they are talking about. Read below for more information.

The Wi-Fi protocol was not designed for home automation. There is a lot of network communication overhead in Wi-Fi (and also in TCP/IP) transmissions that result in slower performance. This overhead is not particularly noticed when you click on on a link in Amazon to view a product page, but it can become very noticeable when flicking a light switch and expecting the lights to come on immediately. There are other protocols (Zigbee and Lutron's RA2) that were specifically designed with home automation in mind: They are designed for low latency (fast) communications, they use frequencies that minimize radio interference, and are designed to handle dozens of devices efficiently. It can be beneficial selecting HomeKit devices that use these protocols and integrate into HomeKit using Bridges.

A well-designed Bridge provides several advantages over directly-connected Wi-Fi devices:

  • Better performance using protocols specifically designed for quickly delivering commands to smart home devices

  • Reduces the number of devices on your Wi-Fi system

  • When you open the Home App, instead of HomeKit having to send a status update request to each device individually (and wait for each device to respond), it can send a single request to the Bridge, which can provide the answer in a single response

  • If you ever change your Wi-Fi SSID or password, all of your bridge-connected devices will work without changing their settings

This is not to say that Wi-Fi devices don't have their place, they do. But, devices that use bridges should not be dismissed simply because they use bridges, and consideration should be made regarding the number of devices you are going to control and how many you want on your Wi-Fi network. For example, it wouldn't be unheard of to install 70 light switches or light bulbs in your home. Do you want all of those devices connected to your Wi-Fi network, or does it make more sense to have them connected to a bridged system for faster HomeKit responses and more efficient use of Wi-Fi?