Show Voice DSP Commands On Cisco IOS Gateways

This article is a series of IOS commands that deal with DSPs and PVDMs.

To determine the type of PVDM in your router: show inventory

Our router is using PVDM3-64.

“show voice dsp”, “show voice dsp active” and “show voice dsp voice”

“show voice dsp voice”

For example, if you have a PVDM3-64 voice card, and you do a “show voice dsp voice”, you’ll get 64 lines, which correspond to 64 DSP voice channels. That’s the maximum allowed with this type of cards.

Here is the output of the “show voice dsp voice” command, on a voice gateway:

You notice that some channels are “busy” while other are “idle”. We’ve got 64 entries, so all channels of this DSP are used in voice termination.

“show voice dsp” and “show voice dsp active”

What if we want to see only active DSP voice channels? We can get that information with the command “show voice dsp” or “show voice dsp active”:

Normally, you should have the same number of “busy” DSP voice channels in both “show voice dsp” and “show voice dsp active”. However, in a production network, people are constantly making calls. So probably you won’t have the same number in the output of both commands.