HP 200 Series Services And Applications page 238

Shining a Light on FDDI
Technology Overview
The MAC corresponds to part of the data-link layer of the OSI model. The
MAC standard defines the token-passing method as the means for acquiring
access to the ring. It is responsible for frame and token construction, send-
ing and receiving frames on the FDDI ring, and delivering LLC frames.
The LLC service provides the transmission of a frame of data between two
stations. LLC frames carry user information to stations on the ring and also
to the extended LAN.
FDDI also has a process that defines protocols for managing the PMD and
SMF-PMD, PHY, and MAC, called Station Management (SMT). SMT defines
facilities for connection management, station configuration, error recovery,
and the encoding of SMT frames. MAC and SMT frames carry data and
control information for the operation and management of the FDDI network.
The MAC, PHY, and PMD standards were approved by ANSI and ISO by
1990. The SMT standard was approved in 1991. FDDI is the only LAN with
extensive management capabilities as defined in the SMT.
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