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 for the duplicheck functionality.

The duplicheck plugin provides an advanced but very specialized peer identity duplicate checking. It works independent from the ipsec.conf uniqueids feature.

More information may be found at: http://wiki.strongswan.org/projects/strongswan/wiki/Duplicheck

This plugin is now disabled. This package can be safely removed once it's installed.