PCI FDDI Administrator's Guide

PCI FDDI
Topology
Chapter 1 27
Tree of Concentrators Topology
In the tree of concentrators topology, concentrators are wired in a
hierarchical star topology with one concentrator serving as the root of
the tree. This topology provides great flexibility in adding and removing
stations, and changing the LAN without causing disruption.
Figure 1-3
Dual Ring Topology
The dual ring topology consists of a primary ring and a secondary ring.
This topology does not easily accommodate additions, moves and
changes. It is only used with dual-attached stations. If a second fault
occurs, the ring will segment.