Serving area interface
The serving area interface or service area interface is an outdoor enclosure or metal box that allows access to telecommunications wiring.- Access point
- Cabinet
- B-box
- Cross box
- Cross-connect box
- Jumper wire interface
- Outside plant interface
- Pedestal
- Primary cross-connection point
- Secondary cross-connection point
- Telecom cabinet
Function
The SAI provides the termination of individual twisted pairs of a telephony local loop for onward connection back to the nearest telephone exchange or remote switch, or first to transmission equipment such as a subscriber loop carrier multiplexer and then to the exchange main distribution frame.
In the United Kingdom, the components from the PCP onwards to the customer are known as "D-side", and from the PCP back to the MDF as the "E-side". In the United States, the connection back to the MDF is known as the F2 and/or the F1 pairs.
SAIs are used in suburban and low-density urban areas, serving some of the same purposes that manholes do in high-density urban areas. Besides a cross connect point, they sometimes contain a DSLAM or more rarely a remote concentrator or both.
