In an environment where extended coverage is needed, but access to the backbone is not practical or available, a wireless repeater can be used. A wireless repeater is simply an access point that is not connected to the wired backbone. This setup requires a 50% overlap of the AP on the backbone and the wireless repeater, as shown in Figure .

The user can set up a chain of several repeater access points. However, the throughput for client devices at the end of the repeater chain will be quite low. This is because each repeater must receive and then re-transmit each packet on the same channel. For each repeater added to the chain, throughput is cut in half. It is recommended that not more than two hops be used.

When configuring repeater access points use the following guidelines:

• Use repeaters to serve client devices that do not require high throughput. Repeaters extend the coverage area of the WLAN, but they drastically reduce throughput.
• Use repeaters when client devices that associate with the repeaters are Cisco Aironet clients. Non-Cisco client devices sometimes have trouble communicating with repeater access points.
• Use omnidirectional antennas, like the ones that ship with the access point, for repeater access points.

Generally within buildings, the availability of Ethernet connections is fairly pervasive. Repeaters can be used to extend APs from the building edge, to the surrounding outdoor portions of the building, for temporary use. For example, one customer could use repeater-mode APs to extend coverage into the parking lot during spring sales for a grocery store.

The client association is assigned to the wired/root AP and not to the AP acting like a repeater.