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Conferencing ,Transcoding and PSTN access on same NM-HDV Card

I have a 3725 with a NM-HDV with a 2 X E1 card and 5 PDVM. I will only be using one of the E1 circuits for PSTN and would like to use any spare DSP resources for conferencing

This Url seems to suggest that you can have all these functions on the one NM-HDV card using IOS 12.2(13)T.

Has anybody achieved this? How do you allocate the PDVM resources or is this done automatically?

Please help.


Re: Conferencing ,Transcoding and PSTN access on same NM-HDV Car

Inorder to provision DSP resource for either Conferencing or Transcoding, you need to specify which module is going to be the dspfarm:-

voice-card 1


dsp services dspfarm

The next step is to configure the SCCP (skinny)source interface:

sccp local fastethernet 0/0

sccp <-- enables sccp

Then assign which callmanger the dsp resources register with:-

sccp ccm priority 1

sccp ccm priority 2

Specifying priority for differing callmanagers will enable the resources to re-register with a secondary callmanager.

Finally configure how the DSP resource are allocated, the following example sets the maximum number of conferences provide by the DSPFARM:-

dspfarm confbridge maximum sessions 7


All that remains is to create the media resource within CallManager for either a Hardware Conference Bridge or Transcoder. You simply specify the MAC of the source interface you configured for sccp. (show int fa 0/0)

I have successfully implemented the above on a 3725 with an NM-HDV with 2x E1, although I was using 12.2.(15)T5.

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Re: Conferencing ,Transcoding and PSTN access on same NM-HDV Car

Can you use the same NM-HDV module for your PSTN access with conferincing/transcoding or do you need a seperate voice card for the two services?

If it is only one card how do you configure the PDVM between PSTN access and Conferencing/Transcoding?

Thanks for any assitance

Re: Conferencing ,Transcoding and PSTN access on same NM-HDV Car

NM-HDVs need not be a PDVM for the DSP Resource Pool functionality to operate.

DSPs to voice channels are statically mapped at configuration time, if there are not enough DSPs left on the NM-HDV, the configuration of the ds0/pri-group will not succeed.

I have successfully configured both on the same card, I simply configured one of the remaining E1 ports as an MGCP endpoint.

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