When is pvdm required on voice router 8200

[adeebtaqui]

Under what scenario and When is it necessary to have PVDM installed on voip router like 8200 4000

Does this apply to voip router cme directly connected to service provider sip line?

Is this needed on srst voip gateway router?

[b.winter]

PVDM is needed for Transcoding, Conferencing and MTP or when you have PRI interfaces.

SIP Trunks to provider or CME / SRST itself don't need PVDM. Except if you have to transcode between codecs, or want to host conferences on the router.

[Nithin Eluvathingal · Accepted solution]

This is required when you have isdn line,

if you are using hardware conferencing, mtp transcoding   etc..

If you have a pri lines on srst router yes you need the pvdm to use it during srst.

you need pvdm if you need to do hardware transcoding, conferencing etc even when connecting cme directly with ISP  sip lines.

[adeebtaqui]

How to decide what pvdm size needed

Pvdm 32 or 64

[b.winter]

depends on the requirements you have (how many pri lines, how many transcoder, conference, ... sessions, ...) there is no general rule for that.

[b.winter]

I would also appriciate it, if I also get an "accepted solution" ...

[Nithin Eluvathingal · Accepted solution]

If you use it for isdn connectivity the thumb rule is to use number of channels*1. Which means you need 1 dsp for one channel.

for transcoded, mtp , conferencing there is tool called dsp calculator make use of it to size it properly 

the tool has been updated recently and it’s much more better.

https://dsp-calc.cisco.com