Cisco BPX 8650, Руководство по установке и настройке

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 1 The BPX Switch: Functional Overview
Switch Software Description
The following are three configurable parameters to configure the rerouting groups:
• Total number of rerouting groups
•
Starting load size of first group
•
Load size range of each group
You configure the three routing group parameters by using the cnfcmparm command.
For example, there might be 10 groups, with the starting load size of the first group at 50, and the
incremental load size of each succeeding group being 10 cells. Then group 0 would contain all
connections requiring 0 to 59 cell load units, group 1 would contain all connections requiring from 60
to 69 cell load units, on up through group 9 which would contain all connections requiring 140 or more
cell load units.
An example of the routing group configuration is listed in Table 1-2.
Cost-Based Connection Routing
In standard Automatic Routing Management, the path with the fewest number of hops to the destination
node is chosen as the best route. Cost-based route selection uses an administrative trunk cost routing
metric. The path with the lowest total trunk cost is chosen as the best route.
Cost-based route selection is based on Dijkstra’s Shortest Path Algorithm, which is widely used in
network routing environments. You can use cost-based route selection, such as cost-based Automatic
Routing Management to give preference to slower privately owned trunks over faster public trunks that
charge based on usage time. While providing a more standard algorithm for route selection, network
operators more have control over the usability of the network trunks.
Table 1-2 Routing Group Configuration Example
Routing Group Connection Cell Loading
0 0 to 59
1 60 to 69
2 70 to 79
3 80 to 89
4 90 to 99
5 101 to 109
6 110 to 119
7 120 to 129
8 130 to 139
9 140 and up