Specifications

3/11/98 12:33 General Token Ring 2-1
Chapter 2
Functional Description
2.1 Introduction
This chapter provides a basic introduction to Token-Ring and Ethernet
Operation, and describes the functional operation of the RADring Hub and
each of the modules.
2.2 General Token Ring
Logical Topology
In a Token Ring LAN, computers, devices and stations are connected in a
closed path called a ring. The data signal is transmitted from one station to
the next on the ring, and retransmitted by every active station on the ring
(see Figure 2-1).
The transmission of data on the ring is synchronized by circulating a single
special frame, called a “free token”. A token is an access-granting frame that
circulates from node to node. A node may transmit a data packet only after
it receives the free token. Only one node can have control of the token at
any one time, thereby preventing data collisions (two or more nodes
attempting to transmit at the same time).
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DIRECTION OF SIGNAL PROPAGATION
NODE D NODE C NODE B
MAIN RING
NODE A
Figure 2-1 Token Ring Logical Topology