Cisco IGX 8400 Series Switches

Field Notice: D4 AMI Line Coding on the IGX UXM Card Not Functioning Properly

December 31, 1998

Products Affected

IGX Universal Switching Module (UXM)

Problem Description

The D4/AMI trunk will not come up on the UXM single T1 or UXM inverse multiplexing for ATM (IMA). It is, however, a configurable option when configuring the trunk.


Alternate mark inversion (AMI) line coding is not a supported feature in ATM. Because the UXM is standards-based, AMI is not supported.

Problem Symptoms

The trunk reports an alarm, and does not pass traffic.


Use network trunk modules (NTMs) to connect D4/AMI trunks. Use ESF/B8ZS only for UXM T1 trunks.


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View CSCdk79433 (registered customers only)

For More Information

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