3Com LINKBUILDER 3C18500, User Manual

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9 - 2 C
H A P T E R
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DUA1850-0AAA05
The Token Ring Environment
This section provides a brief introduction to token ring architecture,
followed by a more detailed explanation of token rings within the MSH
chassis. Refer to “ Ring Topology and Sizing ” on page 9-20 for limitations
on ring topology and maximum permitted cable lengths.
If you are already familiar with token ring architecture turn to
Chapter 10 .
Introduction to Token Ring Architecture
A token ring consists of a number of stations connected together in a
logical ring.
Figure 9-1 shows a simple ring of 4 stations with the ring passing
directly from station to station.
Figure 9-1 A Simple Ring
This logical ring is physically configured as a star to improve systems
resilience and management control using one or more Multiple Access
Units (MAUs): see figure 9-2.
A MAU is a wiring concentrator which enables the logical ring to be
configured in the required star topology. Each station is connected to
the MAU via its own shielded or unshielded twisted pair cable, called a
lobe.