Specifications

4-7
Cisco IGX 8400 Series Provisioning Guide, Release 9.3.3 and Later Releases
OL-1166-04
Chapter 4 Cisco IGX 8400 Series Trunks
IGX Trunk Configuration
When the UXM-E reports the back card interface to the NPM, switch software allocates a default number
of UBUs to the card (see Table 4-6). This default number can be changed using the following procedure:
Step 1 Using the switch software dspbusbw command, determine the average used bandwidth for the node.
Note When you use the dspbusbw command, a yes/no prompt asks if you want firmware to retrieve
the usage values. If you enter “y,” the UXM-E reads—then clears—its registers and restarts its
statistics gathering. If you enter “n,” switch software displays the current values stored on the
NPM.
Timesaver The Network Modeling Tool (NMT) helps you estimate the cellbus requirements using the projected
load for all UXM-Es in the network.
Step 2 Using the switch software cnfbusbw command, set the desired cellbus bandwidth allocation for the card.
Step 3 Continue with planning bandwidth usage (see the “Bandwidth on IMA Trunks and Lines” section on
page 4-8).
Table 4-6 Default Cellbus Bandwidth Allocations for UXM-E Interfaces
Interface Type Ports Default UBUs
Default Cell
Traffic (cps)
Default Cell +
FastPacket Traffic
(cps and fps)
Maximum
UBUs
Maximum
Cell Traffic
(cps)
Maximum Cell and
FastPacket Traffic
(cps and fps)
OC3 4 or 2 44 176,000 132,000
88,000
235 708,000 473,000
470,000
T3 6 or 3 24 96,000 72,000
48,000
235 708,000 473,000
470,000
E3 6 or 3 20 80,000 60,000
40,000
235 708,000 473,000
470,000
T1 8 8 32,000 24,000
16,000
32 128,000 96,000
64,000
T1 4 4 16,000 12,000
8,000
16 64,000 48,000
32,000
E1 8 10 40,000 30,000
20,000
40 160,000 120,000
80,000
E1 4 5 20,000 15,000
10,000
20 80,000 60,000
40,000