The UK academic networking community was one of the earliest to attempt to devise a complete set of open systems interconnection (OSI) standards for all aspects of its networking requirements, and to make a concerted effort to apply these to the entire community. A main thrust of the approach was the definition of protocols for each of the major networking requirements, each protocol being issued in a different colored binder. The important protocols were:Colors have been used to identify various other standards, including CD-ROM format standards.
defining a transport service, roughly equivalent to layer 4 of the ISO seven-layer reference model.
defining a terminal connection protocol.
defining a file transfer protocol.
defining an electronic mail service.
defining a job transfer and submission protocol.
defining a transport service to run over an ISO OSI CSMA/CD service.
defining a network service running over a Cambridge Ring.