Local Area High Speed Networks

Summary Points

• A classic half-duplex Token Ring consists of a set of stations connected in a ring. The stations share a 4Mbps or 16Mbps bandwidth.

• The physical wiring of a classic Token Ring looks like a ring of stars. Stations connect to concentrators in wiring closets.

• A token circulates around the ring. A station with data to send captures the token, transmits one or more frames, and then sends a fresh token.

• If early token release is used, a sender transmits a token right after the interframe gap that follows its final frame.

• Frames that contain user data are called LLC frames. Frames that carry various types of protocol messages are called MAC frames.

• The active monitor, which is chosen by an election process, watches over the token protocol. ...