In article , jsandlin0803 wrote: :I am looking at connecting a remote office to the main office for a :static route. I will have a cisco 1721 at the branch, and a 1750 at the :main office. The main office will have a T1, and the branch will have :DSL. Do i need the vpn module to accomplish a vpn connection between :the 2 offices, or is that just extra encription?
As best I recall, the VPN module is just a hardware acceleration, and the software encryptions are available without it, provided that you have the appropriate software image.
The sales documentation on the 1721 VPN Accelerator mentions only
3DES, which is consistant with my memory and with the 830 series' accelerator, which supports DES and 3DES only. But the complete 1700 line supports AES -- and as we know that isn't hardware accelerated, we know that the AES support must be in software, and thus that the VPN accelerator is not necessary for IPSec.
The minimum IOS [modern] feature set for IPSec is Advanced IP Services or Advanced Security. The 1700 is, though, generally available with just the IP Base feature set, so not every 1700 will have software support for IPSec.