Cabletron Systems bridges Manuel D’Utilisation

Page de 132
Network Design
5-16
The Workgroup as the Network
The Workgroup as the Network
In many cases, the only network that a facility requires is a single workgroup. 
Depending on the bandwidth, segmentation, and security requirements of any 
facility, the single workgroup may be all that is needed. In these situations, the 
only network to be considered is the workgroup.
When the only networking concern is the workgroup, issues such as 
internetworking and inter-workgroup communications are not a part of the initial 
design strategy. A single workgroup design can be customized to any extent that 
the Network Designer wishes, without concern for the inclusion of 
internetworking or security. 
It is important in these situations, however, to plan for future expansion. What 
will happen if the number of stations to be placed on the network increases in the 
coming years? How willing are the network’s end users to pay to completely 
replace all the equipment that makes up the workgroup in order to add special 
functions? What actions will be taken if the facility expands or constructs another 
separate office? All of these questions should be examined before selecting a 
single networking product.
The Workgroup in the Larger Network
In most situations, the workgroup is only a part of a larger enterprise network. In 
these situations, consideration must be given to the organization of the enterprise 
network when designing the workgroup. Workgroups in an enterprise network 
quite often have specific internetworking needs. The Ethernet workgroup in the 
Materials Processing department may need a connection to the corporate Token 
Ring backbone network, or the small branch office network may require a Wide 
Area Network connection back to the head offices.
The specific situation faced at any installation site is one of two conditions: either 
the workgroup(s) must be connected to an existing facility backbone or a 
backbone must be set up to connect a series of newly-designed workgroups. The 
sections that follow describe some of the approaches taken to facility backbone 
design, their strengths and weaknesses.