I have few queries about VPN module in 1841 ISR :
a. whether there is On-Board AIM installed in 1841 ?
b. Why we install external(daughter card) AIM-VPN/EPII plus module ?
Are there any serparate commands to enable on board AIM & AIm-VPN/EPII PLUS module ?
I have found out a DMVPN test results document for you, which will give an idea about the router performances using on-board VPN and AIM VPN module:
The native VPN module in all ISR routers is soldered to the motherboard, is not an AIM.
You would install additional AIM modules as required by the cyphered throughput (must be a lot).
There are no commands required to use them, it's automatic.
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