Hardware Reference
In-Depth Information
computertothenetworkbetweenexistingcomputersmightrequirereplacementoftheex-
isting network cable between the computers with shorter segments to connect to the new
computer's network card and T-adapter, thus creating downtime for users on that segment
of the network.
Ring Topology
Another topology often listed in discussions of this type is a
ring
, in which each worksta-
tionisconnectedtothenextandthelastworkstationisconnectedtothefirstagain(essen-
tially a bus topology with the two ends connected). Two major network types use the ring
topology:
•
FiberDistributed DataInterface(FDDI)
—Anetworktopologyusedforlarge,high-
speed networks using fiber-optic cables in a physical ring topology
•
Token-Ring
—Uses a logical ring topology
A Token-Ring network resembles a 10BASE-T or 10/100 Ethernet network at first glance
because both networks use a central connecting device and a physical star topology.
Where is the “ring” in Token-Ring?
The ring exists only within the device that connects the computers, which is called a
multistation access unit (MSAU)
on a Token-Ring network (see
Figure 17.15
).
Figure 17.15
A Token-Ring network during the sending of data from one computer to another.
Signals generated from one computer travel to the MSAU, are sent out to the next com-
puter, and then go back to the MSAU again. The data is then passed to each system in
turn until it arrives back at the computer that originated it, where it is removed from the
