The Internet continues to grow rapidly and networks based on the Internet p
rotocol will be the predominant communications networks as we move into the
21(st) century. Limitations in Version 4 of the Internet protocol have led
to the development of a new version of the protocol, IPv6. This article lo
oks in detail at the next generation Internet protocol (IPv6), the issues s
urrounding its introduction, and experimental work conducted in BT's Future
s Testbed and the 6bone.