HDLC Modes of Operation

The HDLC protocol is a general purpose data link control protocol capable of supporting a range of modes of operation. The two most prevalent modes are:

Be-aware of transmission bit-order

Many books describing HDLC follow the ISO standard which defines the protocol. This describes the format of the HDLC control word according to the order in which the bits are transmitted at the physical layer. (i.e. least significant bit (lsb) transmitted first). To present a consistent view of all protocols, this course will describe the format in terms of the bit-order seen by the computer and used inside the computer network interface card. See separatesection on bit order.


See also:

HDLC Control Field