Is the Cisco VPN an implementation of some standard protocol?
I know that the ShrewSoft VPN client is able to connect to a Cisco VPN server (I know this because I use it - to bypass the Disallow local LAN access restriction).
Is ShrewSoft VPN, along with Cisco VPN, an implementation of some standard VPN protocol (IPsec + Pre-shared key + XAuth). Or is Cisco VPN a proprietary protocol that ShrewSoft reverse engineered?
Longer story short: would Windows, or a router, be able to connect to a Cisco VPN server using the same protocol that Cisco is?
