DSP usage when voice conference with different location users

[achilles1417]

Hi All,

As titled.

If there are two region for my client

Region A & Region B

The communication with Region A and Region B is using G.729 due to the MPLS bandwidth limitation.

Both Region A & Region B have voice gateway for T1 line with DSP PVDM-3 64 resource.

If Region A user call to Region B user, and then region A user call to third party mobile through Region A T1.

On this situation, may I know whether the DSP usage for:

1. Region A user call to Region B user using G.729

2. Then, Region A user call to third party mobile through Region A T1.

3. Then, Region B user call to third party mobile through Region B T1.

Finally, 4 party conference is made.

Thanks

[Vivek Batra]

1. Since RTP will flow directly between two phones of Region A and Region B, so there won't be any DSP usage.

2. There will be DSP usage because of IP (RTP) to TDM (T1) conversion in Region A voice gateway.

3. There will be DSP usage because of IP (RTP) to TDM (T1) conversion in Region B voice gateway.

4. Depends on who invokes conference and media resources assigned, respective voice gateway DSP's will be aligned for conference (assuming hardware conference here).

Ps: If user (Region A) invokes conference, there will be three parties in total viz Region A user, Region B user and external mobile call made by Region A user. I am not sure if you can include the mobile call in that conference made by Region B user. Same will be applicable when conference is invoked by Region B user.

- Vivek 

[achilles1417]

Hi Vivek Batra,

Thank you for your comment.

One more question, the there are only one Unity Connection on HQ.

If user in remote location is using G.729 to HQ in order to reduce the bandwidth consumption, would the DSP in remote location handle for the G.729 transcoding or the HQ DSP handle for the transocding? Or there are no need for transcode.when using G729 to access voicemail?

Thank you, 

[Manish Gogna]

Hi,

Transcoder can be invoked from any location depending upon which MRGL is applied to the device. Ideally it should be local in case of WAN links. If the entire call flow involves the same codec then no transcoder is invoked, for G729-G711 conversion transcoder would be needed.

HTH

Manish

[Vivek Batra]

Adding to what Manish said, if you enable G729 codec in CUC, RTP can flow directly between phone and CUC and hence DSP won't be required.

- Vivek