Frame synchronization

frame synchronization: Of a received stream of framed data, the process by which incoming frame alignment signals, i.e. , distinctive bit sequences, are identified, i.e. , distinguished from data bits, permitting the data bits within the frame to be extracted for decoding or retransmission.

Note: The usual practice is to insert, in a dedicated time slot within the frame, a noninformation bit that is used for the actual synchronization of the incoming data with the receiver. Synonym framing (def. #1).

Source: from Federal Standard 1037C