Cabletron Systems Cabletron BRIM-F6, Сетевое руководство

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Network Design
5-8 The Role of the Workgroup
Priority organization of this manner in a single-segment network involves
providing stations in the priority workgroups with qualities of media and
network connection based on that priority. For example, the stations in the server
farm might have redundant connections to the network in the event that one cable
failed, use a media resistant to interference, such as fiber optic cabling, or might
be best served by a centralized location. A priority organization workgroup or
sub-section of a workgroup that is located on the same network segment as its
most common users is usually an efficient and safe use of resources, and will not
impede the operation of the network.
While keeping the users separate from the devices that they need to access on a
regular basis does enhance the Network Manager’s control over its use and
operation, it does reduce network performance in networks using segmentation.
By connecting stations to the network based on their relative importance, the
priority organization method makes little or no accommodation for the
localization of network traffic, which is the purpose of segmentation. If a file
server is located in a server farm workgroup, segmented from the rest of the
network, every user needing access to any file server must cross a segmenting
device such as a bridge or switch, introducing access delays as the device reads in
the packet, examines the packet, determines whether to send it on or discard it,
checks the packet for errors, and acts on its forward or discard decision. The
necessity of crossing the segmenting device on a regular basis destroys the
network availability that is gained by bridging, as local traffic is no longer kept
local.
The use of priority organization also introduces additional troubleshooting
complications. If a station in the Sales department cannot access their file server, is
it because the server has failed, the bridge connecting the server to that
department is in error, the connection from the Sales department to the bridge is
down, or the connection from the employee’s workstation to the rest of the Sales
workgroup is faulty?