Libreswan is a popular open-source VPN alternative that supports common protocols such as IKE and IPsec. IPsec is a meticulous protocol suite that mainly works to secure encrypted data that’s being shared between two parties. Whereas, the IKE executes secure authentication and dynamic key generation for seamless data flow. Both these standard suite protocols are created and maintained by the IETF (Internet Engineering Task Force). Libreswan provides a wide range of security features and uses opportunistic encryption techniques. Libreswan is avalible on Linux and uses repository files and tarbal which makes the installation process as simlpe as possible.