IPsec makes VPN connection possible. I enables to simulate a leased line across public Internet and thus enable us to get secure connection across unsecured environment. It enables encryption, authentication and protection of our data when sent across insecurity of the world’s biggest internetwork – Internet.
It’s the cheap way to simulate a leased line, the way to send private data across the public network without compromising privacy. The goal of IPsec is to secure services and lower the cost of data transfer. Try to compare it to pricing of data transfers across dark cables / leased lines.
There are two parts of IPsec security suite
– ESP – Encapsulating Security Payload
– AH – Authentication Header
Based on our situation we can configure two different modes of operation and here we are to make the things clear about the differences and the technology behind those modes.