We have a spare 3845 that we plan to use in a future VoIP design. It was bought as a security router, so it came with no voice upgrades.
I've been researching what I need to do to upgrade it to support voice.
Our plan is to have three T1s coming in (one from Verizon for outbound calling, two from AT&T for inbound 1800#s). Total number of lines is 60, but I suppose we should plan for a max of 72.
We will be using G.722, which from my reading Cisco tells me is a Medium-Complexity Codec.
So I'll probably need three PVDM2-64? How are these installed on the router, and what is the max on a 3845? It looks like you actually install them on the network module, not the router itself?
Is there a network module that would include the DSPs, or do you always order it seperately?
And lastly, which network modules should I be looking at for voice T1s in my 3845?
To add to Deji's great response, the 3845 router has 4 on-board PVDM slots, each can accomadate up to 64 channel PVDM (PVDM2-64), the router also has 4 HWIC slot where you can insert VWIC2 cards (PRI cards). This solution will be cheaper than getting NM-HDV2 card, but either way will work just fine.
Besides voice termination, you may also want to configure resources for conferencing and/or transcoding. You can use the DSP calculator to come up with the appropriate modules.
To plan the number of dsps you need for your scenario, use the DSP calculator. This is a great tool from cisco to plan your dsp requirement.
Here is the link.
PVDMs are installed in PVDM slots. These slots are located on the motherboard on the router.
Network Modules usually ship with DSPS, you dont have to order it seperately.
For network modules..
Have a look at this doc, it shows the available network modules and the DSPS that come with them.
I did some configs for you..
If you are going to use HWIC cards eg 1 VWIC-2MFT-T1 and 1 VWIC-1MFT-T1 (total is 72 channels)
Then you will need...
one PVDM2-16 + two PVDM2-64
three PVDM2-32 + one PVDM2-48
This is based on medium complexity codec..
codec complexity medium.
If you are going to use network Modules..
eg NM-HDV-2T1-48 in slot 1
and NM-HDV-1T1-24 in slot 2..
Then you do not need to buy additonla dsps as they dsps on this modules are self sufficient.
HTH, please rate useful posts