Preface
This book is about the next generation Internet protocol. We have become familiar with the strengths and weaknesses of IPv4; we know how to design and configure it, and we have learned how to troubleshoot it. And now we have to learn a new protocol? Start from scratch? Not really. The designers of IPv6 have learned a lot from over 15 years of experience with IPv4, and they have been working on the new protocol since the early 1990s. They retained the strengths of IPv4, extended the address space from 32 bits to 128 bits, and added functionality that is missing in IPv4. They developed transition mechanisms that make IPv4 and IPv6 coexist peacefully and that guarantee a smooth transition between the protocols. In fact, this was one of the major requirements for the development of the new protocol version.
So you do not need to forget what you know about IPv4; many things will feel familiar with IPv6. When you get started, you will discover new features and functionalities that will make your life a lot easier. IPv6 has features that will be needed in tomorrow’s networks—features that IPv4 does not provide. The day will come when our Personal Digital Assistants (PDAs) and mobile phones have an IP address. Aside from the fact that the IPv4 address space could never cover the demand for that number of IP addresses, imagine configuring those devices with the means we have today!
One of the coolest features built into IPv6 is autoconfiguration capability. Haven’t we always been ...