Installation guide

Release Notes for Cisco Voice Interworking Service Module Release 3.0(0)

Part Number OL-2523-01 Rev. B0, January 9, 2004

Installation and Upgrade Procedures

Note Loading this release of the backup bootcode is required for existing VISM cards not using this new

release.

Limitations and Restrictions

The following limitations and restrictions are valid for software Release 3.0(0) for VISM/VISM-PR:

• The switched AAL2 PVC operating mode is not supported for VISM Release 3.0(0).

• Software Release 3.0(0) for VISM/VISM-PR requires you to use 64 Mb VISM cards or VISM-PR

cards exclusively.

• The switched AAL2 PVC operating mode is not supported in software Release 3.0(0) for

VISM/VISM-PR.

• Cisco recommends that you use the cnfcodecjtrdelay command to configure the jitter-delay

argument to 20 ms when using DSP firmware versions 3.4 and 3.6.

Table 10 describes the design constraint which is identified in software Release 3.0(0) for

VISM/VISM-PR.

Installation and Upgrade Procedures

This section describes the following installation and upgrade procedures:

• “VISM to VISM-PR Upgrade Procedure” section on page 31

• “VISM Firmware Download Procedure for PXM1” section on page 32

• “Installing VISM Software Updates with PXM1 Cards” section on page 33

• “VISM Boot Code Upgrade Procedure with PXM1 Cards” section on page 36

• “VISM Downgrade Procedure” section on page 37

• “Caveats” section on page 38

Caution If you are upgrading the VISM software from 1.5(x), refer to the “Caveats” section on

page 38. VISM Release 2.1(0) does not provide a graceful upgrade procedure from 1.5(x)

to 2.1(x).

Table 10 Known Design Constraint

DDTs Issue Description

CSCdv37382 The addcid command can put VISM into the fail state. If non-AAL5 cells are sent to

an AAL5 PVC of VISM, this can cause the VISM SAR chip to hang and VISM to go

into failed state. This is because, in case of AAL5, the last bit of the Payload type

indicator is used to determine which cell contains the end of that payload. All cells

which have this bit set to 0 are held in the reassembly buffer until the cell with this

bit set to 1 arrives. In case of non-AAL5 cells, this bit will never get set to 1, and

ultimately this buffer will overflow. So, care should be taken that only AAL5 cells are

sent to AAL5 PVCs of VISM.