Let me start by placing the article into the appropriate context.  The key word “Everything” in the title refers to different Cisco IPsec VPN frameworks and of course not to the entire universe. As physicists and scientists have been trying to unify all fundamental interactions, such as gravitation, strong interaction, weak interaction, and electromagnetism, into a single, unifying, all-encompassing Theory of Everything, Cisco engineers have already (almost) succeeded in unifying different IPsec VPN frameworks into a single, comprehensible set of CLI commands, called Cisco IOS FlexVPN.  Not that the two tasks are comparable, though.

One may wonder why the “(Almost)” in the title. The reason is that the unification task has not been completed entirely. FlexVPN encompasses all VPN frameworks that could be used over public networks, such as the Internet, using overlay tunneling. However, FlexVPN does not encompass a GETVPN framework, which can be used only over private networks without overlay tunneling. Therefore it seems that Cisco’s unification attempt has been successful, but only partially.

(To be honest, physicists also made quite some progress in finding the “real” ToE. They are struggling with the last unification step, unification of quantum mechanics and gravitation and many believe that the solution to this unification is the string theory.)

by Tilen Mlakar, Internetworking Expert, CCIE Security #35693