There is no straight answer to your question as it all depends on your current config, RAM and CPU usage, and there are far too many variables to give a yes/no answer.
Yes, the maximum sessions depend on platform and memory, and they're all based on the assumption that the ISR, other than basic networking, will be ONLY doing IOS MTP and keeping CPU below 75%
Obviously if that same ISR has TDM, AAA, H.323, SIP, security, etc resources will be consumed and so on, so the resources for IOS MTP will decrease, and so the maximum number of sessions.
The only way to answer your question is:
A) Hire Cisco Advanced Services so they can lab this up for you and give you the results
B) Do the above yourself.
HTH
java
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