Cabletron Systems Cabletron BRIM-F6, Сетевое руководство

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Network Design
5-20 The Workgroup in the Larger Network
• Simplified Troubleshooting - Workgroups can be bypassed by simply
reconfiguring a single patch panel. This can easily isolate a problem segment
for troubleshooting, and keeps the backbone network from being kept in a
fault condition.
• Moderate Control - The isolation of workgroups and the reorganization of the
backbone network is simplified with the collapsed backbone, but the system
does not incorporate any management features beyond the physical
connections of facility cabling. For advanced and detailed network control
operations, the device collapsed backbone (discussed below) is superior to the
collapsed backbone alone.
Devices as Backbones
Once a collapsed backbone has been designed, it is a simple matter to connect the
multiple backbone cables together through a device. Often this device is a
multiport router, network switch, or a modular chassis. The use of a device of this
type to make the connections between workgroups greatly increases the control
that Network Managers have over the network, and may improve performance
by streamlining the communications between networks.
Figure 5-7. Device Collapsed Backbone
The device collapsed backbone is the most expensive backbone because of the
added cost of sophisticated, high-performance hardware to the costs of a
collapsed backbone cabling layout. In many cases, the additional control and
functionality of the device collapsed backbone configuration are so valuable that
the cost is well worth it.
• Connectivity Requirements - The device collapsed backbone implementation
brings all cables of the backbone to a single device, which takes care of the
interconnection issues.
• Ease of Expandability - As all the workgroups of the network are connected
through the backbone device, the expandability of the network is limited by
the amount of expandability that the device is capable of. As with the design
of facility cabling, planning for future needs will go a long way toward
reducing future expenses and possibly avoiding a costly replacement upgrade.
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Ethernet Switch
2094n12