Components and Topologies
Access points

An access point (AP) contains a radio transceiver. It can act as the center point of a stand-alone wireless network or as the connection point between wireless and wired networks. In large installations, the roaming functionality provided by multiple APs allows wireless users to move freely throughout the facility, while maintaining seamless, uninterrupted access to the network.

APs come with varied technology, security, and management features. Some APs are dual-band and support both 2.4-GHz and 5-GHz technologies, while others only support a single band. If an AP has a nonvolatile FLASH ROM to store firmware and configurations, it is easier to update firmware and change configurations. Any AP can be used as a repeater, or extension point, for the wireless network. Figure illustrates the Cisco Aironet 1100 and 1200 APs. The Aironet 1100 supports 802.11b and the Aironet 1200 is a dual-band AP that supports both 802.11b and 802.11a. Both devices will be upgradeable to 802.11g with a mini-PCI replacement.