Bridges and repeaters perform very different roles in a network, although both are used to extend network coverage. Repeaters simply relay a Wi-Fi signal, helping to extend the range of a given wireless network. Bridges, on the other hand, use wireless signals to join two existing networks together into one larger network.

Function of Repeaters

Wireless repeaters are designed to rebroadcast wireless signals. When a repeater receives a wireless signal, it re-transmits the data it has been sent without changing that data in any way. This re-transmission helps users to avoid the effects of attenuation, a process by which wireless signals become degraded as they travel through the air. Using a web of repeaters means that signals only ever have to travel over short hops, even when they are intended for clients a long way away from the original access point.

Function of Bridges

Unlike repeaters, wireless bridges are network clients in their own right. Pairs of bridges are used to create a wireless link between two networks, allowing the devices on one network to see the devices on the other as if they were part of the same local network. For example, if a school has separate networks in two adjacent buildings, by adding a bridge to each of the networks and configuring the bridges to communicate, the school can unify the networks into one large setup.

When to Use Repeaters

You should use repeaters if you want to add a couple of extra long-range clients to a network, or to improve the performance obtained by the clients at the very edge of your existing wireless network. Repeaters are not usually a practical way of extending network coverage to many devices, as the transmission quality of a wireless signal decreases slightly every time the signal is repeated. As such, repeated signals may not have the bandwidth to provide an acceptable service to large numbers of clients.

When to Use Bridges

Bridges are best if you need to significantly extend the range and scope of a wireless network. By dividing your machines into two networks and linking them by a bridge, you may get better overall performance than you would from a web of repeaters. You can also use most bridges to connect a wired device to a wireless network, as bridges can usually connect to both wired and wireless clients. In this instance, the bridge effectively acts as a wireless adapter.