Components
Antennas

Cisco Aironet 2.4 GHz access points are available with either captive dipole antennas or reverse Threaded Naval Connector (TNC) connectors, which enable a customer to attach different types of antennas. Users can choose the right antenna for their application from a broad selection of Cisco products, which are pictured in Figure .

Cisco Aironet AP 2.4 GHz antennas are compatible with all Cisco RP-TNC equipped APs. The antennas are available with different gain and range capabilities, beam widths, and form factors. Coupling the right antenna with the right AP allows for efficient coverage in any facility, as well as better reliability at higher data rates. A detailed coverage of antennas will be provided later in the course.

Cisco Aironet bridge 2.4 GHz antennas provide transmission between two or more buildings. Cisco has a bridge antenna for every application. These antennas are available in directional configurations for point-to-point transmission and omnidirectional configuration for point-to-multi-point implementations. For distances of up to 1.6 km (1 mile), Cisco offers an omnidirectional mast mount. For intermediate distances, Cisco offers a Yagi mast mount and an omnidirectional mast mount. The solid dish provides connections of up to 40 km (25 miles). Cisco Aironet bridge antennas are shown in Figure .

Antennas operate at Layer 1 of the OSI Model, as shown in Figure . Remember that the physical layer defines the electrical, mechanical, procedural, and functional specifications for activating, maintaining, and deactivating the physical link between end systems. Characteristics such as voltage levels, timing of voltage changes, physical data rates, maximum transmission distances, physical connectors, and other, similar, attributes are defined by physical layer specifications.