(IPv6 is an alternative protocol to IPv4 and is the central and basic protocol of the next generation Internet. Since 1994 when the IETF agreed to RFC1752, IPv6 has gone through a long-term development process. Today, IPv6 is now standing on the threshold of large-scale commercial use. It is recognized in the industry that IPv6 will comprehensively promote the development of a series of new services and new technologies represented by mobile communications and digital home appliances, and serve the whole society.)