The strongSwan VPN suite uses the native IPsec stack in the standard Linux kernel. It supports both the IKEv1 and IKEv2 protocols.

This package provides the strongSwan plugin which provides an IPsec backend that works entirely in userland, using TUN devices and strongSwan's own IPsec implementation libipsec. This is useful for when there is no kernel support for IPsec.

This plugin is now included in libcharon-extra-plugins. This package can be safely removed once it's installed.