Openswan is described as 'IPsec implementation for Linux. It has support for most of the extensions (RFC + IETF drafts) related to IPsec, including IKEv2, X.509 Digital Certificates, NAT Traversal, and many others' and is an app in the Security & Privacy category. There are three alternatives to Openswan for Linux, Mac, Android and BSD. The best alternative is strongSwan, which is both free and Open Source. Other great apps like Openswan are IPsec-Tools (Free, Open Source) and Libreswan (Free, Open Source).