This is complemental support for the IP version 6.
You will still be able to do traditional IPv4 networking as well.

For general information about IPv6, see
<http://playground.sun.com/pub/ipng/html/ipng-main.html>.
For Linux IPv6 development information, see <http://www.linux-ipv6.org>.
For specific information about IPv6 under Linux, read the HOWTO at
<http://www.bieringer.de/linux/IPv6/>.

To compile this protocol support as a module, choose M here: the
module will be called ipv6.

source code:

net/ipv6/