This chapter covers the following key topics:
IP version 6 (IPv6) is designed to be the new generation of the IP protocol, following IP version 4. The number 5 had already been assigned to another Internet protocol, the Internet Stream Protocol, version II, as defined in RFC 1190. A detailed description of all IPv6 components is beyond the scope of this book, but this chapter thoroughly summarizes the design goals of IPv6 and the current state of the protocol. This chapter also covers IPv6 packet format, IPv6 functionality, and methods to get from IPv4 internetworks to IPv6 internetworks. The Cisco router configurations shown in this chapter are created using beta software that is based on IOS 12.0. Commands may be modified, added, or deleted, and output may be modified in the final version of the code, although any changes will probably be minimal. Cisco has announced that the production code will be in a later version of Cisco IOS Software Release 12.1.