ABM - technical definition

A peer-to-peer mode of asynchronous communications in which either of a pair of devices can initiate a transmission and send data over a point-to-point link at any time. ABM is a communication mode used in High-level Data Link Control (HDLC) and derivative protocols, such as Link Access Procedure-Balanced (LAP-B). See also asynchronous, HDLC, LAP-B, link, master/slave, and point-to-point.