A Link-Level protocol used to facilitate reliable point-to-point transmission of a data packet.

A bit oriented data link control that is functionally similar to Advanced Data Communications Control Procedures (ADCCP).

a bit-oriented framing and addresing scheme defined in ISO 3309 that is used as the basis for most modern synchronous wide-area data communications protocols, including PPP, X.25, SNA, OSI, and Frame Relay.

A data link layer protocol.

A form of communications line control that uses a specified series of bits rather than control characters to control data transmission over a communications line.

In data communications, the use of a specified series of bits to control data links in accordance with the International Standards for HDLC: ISO 3309 Frame Structure and ISO 4335 Elements of Procedures.