Increasing the number of Wi-Fi access points provides network redundancy, better range, support for fast roaming and increased overall network-capacity by using more channels or by defining smaller cells. Except for the smallest implementations (such as home or small office networks), Wi-Fi implementations have moved toward "thin" access points, with more of the network intelligence housed in a centralized network appliance, relegating individual access points to the role of "dumb" transceivers. Outdoor applications may use mesh topologies.
When multiple access points are deployed they are often configured with the same SSID and security settings to form an 'extended service set.' Wi-Fi client devices will typically connect to the access point that can provide the strongest signal within that service set.