Cisco VCO/4K Open Programmable Switches

Field Notice: VCO Deleted ICC Span Maintains Original Timeslot Assignments

September 21, 1999

Products Affected



VCO-ICC= 50288080150

Interface Controller Cards installed on VCO-4K, VCO-20 or VCO-80 with any T1, E1 or J1 I/O module operating the following levels of Generic Call Control Software are impacted:

  • All version 5.x releases:

    • V5.1FSR00PUN00 through V5.1FSR00PUN00PUN24.

    • V5.0FSR00PUN00 through V5.0FSR00PUN26.

Problem Description

When an ICC span is deleted from the database, the ICC continues to transmit on the timeslots that were assigned to it before its deletion from the database. This problem occurs when this or another span is added to the database. The Generic Call Control software dynamically re-assigns to the recently configured span, which are the same timeslots that were used by the deleted ICC span. The ICC continues to transmit on these timeslots. The result is extraneous transmissions on the re-assigned timeslots.


The VCO Generic Call Control software dynamically assigns timeslots as physical cards are added to the database. Under normal conditions, when ICC spans or physical cards are removed, these timeslots are re-assigned and the ICC will stop transmitting on them. When this problem occurs, the timeslots are being re-assigned by the Generic Call Control software, however the ICC continues to transmit on them.

Problem Symptoms

Anomalous noise, tones, or no voice path is present on calls that are serviced by timeslots which have been impacted by the ICC span's transmissions.


There are three workarounds:

  1. Avoid deleting ICC spans from the Generic Call Control database until a software resolution is available.

  2. Taking the entire ICC out of service after the span has been deleted from the database will prevent this problem from occurring. To accomplish this through the System Administration's Card Maintenance menu, change the status of the entire ICC (Rack-Level-Slot) to Out Of Service. This will change the status of all spans associated with that ICC to Out Of Service. Then change the ICC card status (Rack-Level-Slot) to Active. This will reboot the ICC and prevent extraneous transmission on re-assigned time slots.

  3. Remove the ICC from the VCO backplane and then reinsert it. This action will reboot the ICC and prevent extraneous transmission on re-assigned time slots. Refer to the "VCO/4K Card Technical Descriptions" for removal and replacement procedures.

Option one has the advantage that it does not require any resets and the inherent loss of calls on other spans of the same ICC as the card resets itself.

A software resolution to this will be integrated in V5.1FSR00PUN26.


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CSCdm90533 (registered customers only)

Deleting one span from ICC causes voice path problems.

For More Information

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