It seems like it would be able to do more. If I am doing G.711 then I'd only need 11 PVDM2-64's to aggregate an entire DS3. That would mean I'd need 3 slots leaving 3 available. So, are any of those configurations able to run simultaneously? Perhaps a 8 CT1/CE1 along with the CT3? What could I do with the rest of the slots available?
You can probably get more interfaces in the router, but you're at risk of going over the amount of calls per second on the box. There was a discussion on another thread about how going over the suggested amount may cause for you to have a lack of support with development/TAC as well if something tricky comes along.
That being said, you may want to look at the VGD-1T3 also. To be honest, I'm not certain of the hardware or price differences between getting a 5400XM with the AS-5X-FC cards and a T3 and just using the VGD-1T3.
I do know that the VGD-1T3 has CUCM MGCP support and also supports conferencing and transcoding, however. It may be worth looking at.
The data sheet is here, which also lists 672 calls:
What you're forgetting here, is that routers / access servers / whatever, are not just interface card holders with infinite capacity.
So, if cisco says they can do 672 calls, probably some engineer and test engineer estimated and verified the CPU / bus / whatever capacity to be in that maximum range.
I also think that is not very nice to be find yourself in deep s*it just because you wanted to squeeze something more out of an expensive piece of equipment that uses an expensive circuit. It's not as if you're saving your own money after all.
And, how do you know if cisco didn't put a specific software limitation to prevent people running unsupported configurations ...
Seems strange they would allow that and not the ability to have 2xCT3 cards and split the load 384/384 going VoIP->TDM. I wish someone has seen 1 CT3 and several T1's doing VoIP->TDM in the same chassis.
I do not see anything in the data sheet or documentation that prevents you from using two CT3s as long the total number of calls is kept within the published limits.
In fact two CT3s are explicitly supported in case you need to do some TDM switching.
These boxes are market leaders since more than 10 years and can do a lot, but are not infinite after all. You probably just need to get acquainted with them to understand the best way to put them to use.
I had a sales guy that has access to the configuration tool try to configure one with two CT3s and it gave a warning stating it would only do TDM switching. So, that's the reason I'm trying to see if I can have a CT3 along with several T1 interfaces. It's not apparent from the documentation I have read. I wonder if anyone else has seen this configuration in production. It would be a waste of time/money to buy T1 interfaces if they don't work for what I'm trying to do which is VoIP-to-TDM.
The configuration tool is not perfect and cannot guess the intended use for all configurations.
If I know a little about the platform (I should), you should be fine with mix and match interfaces as long the total number of call is not exceeded.
Then again I don't have the proof in hand to show you that, perhaps somebody else has.