Cabletron Systems bridges Manuel D’Utilisation

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The Workgroup in the Larger Network
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Network Design
The Collapsed Backbone
It is also possible to run cables from a central point, often a network management 
office or central wiring closet, out to each workgroup network and back. These 
cabling runs are then terminated at a central point such as a patch panel. The 
patch panel ports for each of the cable runs can then be connected to one another 
using jumper cables. As long as technology restrictions are not exceeded, chains 
and rings of workgroup networks can be created.
Figure 5-6. Collapsed Backbone
Having the individual cable runs of the backbone connected to one another at a 
single point can make this configuration more expensive than the distributed 
backbone, however the added configuration and control options provided by the 
collapsed backbone often outweighs the associated costs.
Connectivity Requirements - The collapsed backbone implementation brings 
all cables of the backbone to a central point, and the requirements of the Token 
Ring and FDDI technologies for an unbroken ring still apply.
Ease of Expandability - Since the cables of the collapsed backbone originate 
from a patch panel in one location, adding new cable runs to accommodate 
new workgroups or to bypass outmoded ones is a simple matter of changing 
a few jumper cables. If the network cabling was planned far enough in 
advance, the facility cabling required to add new workgroups to the backbone 
network may be already in place, requiring only a set of jumper cables and a 
short amount of time to connect. The use of a collapsed backbone can ease the 
transition from a backbone network with no controlling hardware to a device 
collapsed backbone in the future.
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Cross-Connected
Patch Panel
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