Network Design
•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.
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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.
The Workgroup in the Larger Network |
