Specifications

2-24
Cisco IGX 8400 Series Provisioning Guide, Release 9.3.3 and Later Releases
OL-1166-04
Chapter 2 Cisco IGX 8400 Series Cards
Universal Switching Module
Note Information for the enhanced universal switching module (UXM-E) also applies to the UXM. For
differences between the two cards, refer to the release notes for your card.
The enhanced universal switching module (UXM-E) provides ATM trunk and line service for the IGX.
In trunk mode, the UXM-E supports network trunks and in port mode, the UXM-E supports either an
ATM user-to-network interface (UNI) or a network-to-network interface (NNI). The back cards support
multiple physical connector types, with ports operating at OC3/STM1, T3, E3, T1, or E1 rates.
The UXM-E can transport ATM cells to and from the IGX cellbus at a maximum rate of 310 Mbps in
each direction. This maximum rate applies regardless of back card type.
Switch software limits the number of logical trunks and lines that can be configured on an IGX node as
shown below:
• Maximum number of logical trunks on an IGX node: 32
• Maximum number of lines on an IGX node: 64
These limits are independent of the number of UXM or UXM-E cards in the IGX switch chassis, because
switch software monitors the number of configured lines and trunks, not the number of cards that are
physically present.
When you reach these limits, switch software prevents activation of additional trunks or lines on the
node, and you see an error message.
The UXM and UXM-E also support the following features for both trunk and port modes:
• Enhanced ABR support for connections with non-ATM AAL5 traffic to minimize the risk of RM
cell starvation.
• Allows 8000 connections in either trunk, port, or mixed modes.
Note The UXM and UXM-E cannot support more than 4000 gateway connections. All remaining
connections can be user or networking connections. For example, if you configure 2500
gateway connections onto a UXM-E, you still have 5500 possible user or networking
connections.
• Supports 8000 connections concurrently with level-1 and level-2 statistics, and 4000 connections
with level-3 statistics.
• Provides real-time statistics counters and interval statistics collection for ports, lines, trunks, and
channels.
• Supports arbitrary assignments for VPIs and VCIs for each virtual circuit (VC).
• Supports ATM standards-based inverse multiplexing (IMA) to allow logical trunk or line formation
from a grouping of more than one T1 or E1 interface.
• Provides 128,000 cell buffers.
• Uses all four lanes on the IGX cellbus.
• Supports Y-cable redundancy with hot standby.
For information on initial configuration of a UXM-E, see the “UXM-E Configuration” section on
page 2-33.