Complex sentence: The cjdns program talks to other programs on the computer through a TUN device which the computer sees as a regular network connection so any application which speaks IPv6 can communicate in a cjdns based network without any modification.
Split into simpler sentences: The cjdns program talks to other programs on the computer through a TUN device which the computer sees as a regular network connection. Any application which uses IPv6 can communicate in a cjdns based network without any modification.