balanced asynchronous class (BAC)

Balanced AsynchronousClass (BAC) is an asynchronous operating mode of High Level Data Link Control ( HDLC). In BAC mode, the individual stations have the same operating functions and can participate in the communication with equal weighting. The Balanced Asynchronous Class is used in the Link Access Procedure Balanced ( LAP B), which is located on the security layer in the X.25 protocol.