Local Area High Speed Networks

Classic Token Ring Protocol Elements

The sections that follow outline the major features of the classic Token Ring protocol, including

• Token Ring MAC addresses

• The Token Ring format

• LLC frame formats

• MAC frame formats

• Parameters

• Routing information

• Timers

• Types of MAC protocol frames

Addresses

The IEEE LAN addresses described in Chapter 2, "LAN MAC Addresses," are used in Token Rings. However, these addresses are used in a special manner:

• Each address byte is written in reverse order. The first bit of a destination address indicates whether it is an individual address (0) or a group address (1). The second bit indicates whether it is a universal (0) or local (1) address.

• The first bit of a source address is set to 1 to indicate that that a routing ...