As we know, an access point (abbreviation ‘AP’) is a networking hardware device that allows a Wi-Fi device to connect to a wired network. The AP usually connects to a router (via a wired network) as a standalone device, but it can also be an integral component of the router itself.
A bridge is a computer networking device that creates a single aggregate network from multiple communication networks or network segments. This function is called network bridging. In the OSI model, bridging is performed in the first two layers, below the network layer (layer 3). If one or more segments of the bridged network are wireless, the device is known as a wireless bridge and the function as wireless bridging.
Comparing those two in wireless level, that is, to compare wireless bridge with wireless access point. Since both of them have overlapping areas of functionality, there seems to be confusion regarding how they differ from each other.
Wireless Bridges
A computer network tends to be divided into various segments that need to be integrated together. A network bridge connects such divided network segments together, facilitating data sharing. Before the advent of Wi-Fi technology, network bridges were connected through wired ethernet cables. Specifically, in context of the OSI model, network bridges connect segments on layer 2 (data link layer).
These are intelligent devices compared to hubs and repeaters, that control data flow to and fro, from the connected network segments. A wireless bridge performs the same function of linking network segments, but it does that through a Wi-Fi link, instead of a wired ethernet link. It can connect two networks together with a radio link, to facilitate connectivity and data transfer between them.
Such bridges may also be used to connect an ethernet network, with an access point or wireless router, for Internet connectivity. Using a ‘Wireless Distribution System’, bridges are set up to connect multiple networks. There are more than one types of wireless bridges, ranging from basic ones, which facilitate ethernet connectivity with a wireless access point, to ones that double up as a wireless access point and a bridge. That seems to be the source of confusion between the two devices.
Wireless Access Points
Wireless access points primarily provide Internet access by connecting wireless devices with routers. They act as extenders of a Wi-Fi network, by directly providing Internet access over long distances. Popularly known as ‘Wireless Hotspots’, they are some of the most widely used networking instruments. Thus a wireless access point provides Internet and LAN connectivity to multiple devices simultaneously.
Some wireless access points also provide the functionality of a wireless bridge, by providing connectivity between two wireless networks. Modern access points can connect more than 200 wireless devices simultaneously. Some wireless access points are in fact wireless routers which directly provide Internet access, through connection with a modem.
Wireless Bridge vs. Access Point
Firstly, look at the simple illustration of wireless bridge and Access Point:
Wireless Bridge
— —— —
AP
——-
In the *strict* use of the terminology, the following does NOT work
— —— —-
The AP cannot associate with an AP.
With that being said, this is usually a software limitation and a lot of AP’s can actually function as a bridge.
The central point of difference between the two devices lies in their functionality. While wireless bridges are designed to integrate two physically separated networks through a radio link, an access point connects multiple wireless devices with a router. Thus, a wireless bridge connects two computer clusters together and a wireless bridge connects multiple devices with a single Internet connection simultaneously. A bridge can also be used to connect an existing ethernet network with an access point.
Though wireless bridges and access points were separately manufactured before, today a combination of these two devices is more popularly used. These devices offer both bridging and multiple device wireless connectivity. Therefore, the boundary between the functionality of both devices has become blurred. If you are thinking of buying a wireless access point/bridge device, make sure that you go for a 802.11n wireless networking standard based device, which offers the highest data transmission speed currently.
Related reading: Access Point vs. Wireless Bridge