Digital Data Communications Message Protocol
The Digital Data Communications Message Protocol (DDCMP) is a byte-oriented data communication protocol for use over full-duplex and half-duplex point-to-point and multi-drop links; principally using using synchronous or asynchronous serial lines, although other communication channels were also supported. It used CRCs to allow transmission errors to be detected; sequence numbers allow detection of completely lost messages. Retransmission is used to correct both.
- 'DDCMP Specification Version 4.0', AA-D599A-TC (1 March 1978)
- Digital Data Communications Message Protocol (DDCMP) - Contains a good, detailed description of failure modes