Generically, any computer or device in a network that users can gain access to can be called an access point.
In most cases, an access point is a base station in a wireless LAN. Although there are other wireless technologies that use access points, the term generally refers to a Wi-Fi network. Access points (APs) can be stand-alone devices that plug into a router or switch; however, access point functionality is also built into a wireless router, which is widely used in most homes and small offices (see wireless router
Like a Cellular Phone System
Multiple access points can be deployed in an organization, and users roaming with their mobile devices are handed off from one access point (AP) to another.
AP Name = Service Set Identifier (SSID)
Wi-Fi networks are assigned a name by the user or network administrator. When devices search for Wi-Fi networks, they display the names, called "service set identifiers" (SSIDs), of all the Wi-Fi access points in the vicinity. For more details, see SSID
. See virtual access point
and wireless LAN
Access points (APs) are similar to cellphone towers, but transmit shorter distances. Their coverage ranges from as little as 50 feet in diameter to as far as 1,000 feet with amplification. Mobile users are automatically handed off from one access point to another as they meander.
First 802.11 Access Point
The InTalk WR1200 was the first access point (AP) to conform to the IEEE 802.11 standard. Introduced in 1998, the unit supported a maximum rate of 2 Mbps. (Image courtesy of Jod Edney.)
External and Internal Antennas
APs are available with external antennas like our desktop example (top) as well as ceiling mounted with internal antennas (bottom).
There Is an Antenna Inside
Open up the ceiling-mounted access point (previous image), and you find the antenna inside the case.