IEEE Standard for Information processing systems -- Local area networks --Part 4: Standard for Token-Passing Bus Access Method and Physical Layer Specifications

This local area network (LAN) standard deals with all elements of the token-passing bus access method and its associated physical signaling and media technologies. To facilitate interconnection of stations by way of a LAN using the token-passing bus access method, this standard specifies the characteristics of the transmission medium; the signaling method used; the frame formats transmitted; the actions of a station upon receipt of a frame; the services provided at the conceptual interface between the Medium Access Control (MAC) sublayer and the Logical Link Control (LLC) sublayer; and the actions, entities and values used by management. There are four medium characteristics and signaling methods: 5 and 10 Mb/s phase-coherent FSK; 1, 5, and 10 Mb/s broadband; 10 and 20 Mb/s fiberoptic; and 1 Mb/s phase-continuous FSK.