TABLE OF CONTENTS The Domain Name System (DNS) is one of the most fundamental components of today's Internet. In fact, most Internet applications, including e-mail and WWW, depend on the DNSin some way. This is also the case for applications that support IPv6 and for new IPv6 specific applications.
DNS is flexible enough to support IPv6 with straightforward extensions. Still, there are some nontrivial issues regarding IPv6. This is partly because the DNS itself is an Internet application, and the use of the DNS over IPv6 introduces a new level of complexities which are not seen with only IPv4. Also, there are known misbehaviors in some existing DNS implementations that handle IPv6 extensions to the DNS in an inappropriate way, causing trouble not only for IPv6 users but also for those who do not use IPv6. It is therefore important for all kinds of Internet users and developers to understand how the DNS operates with IPv6.
This chapter describes the DNS protocol specification and implementation, focusing on IPv6-specific topics. It begins with a general description of the DNS protocol, followed by an explanation of extensions for IPv6 along with discussions on IPv6-specific issues. Next, it describes KAME's DNS resolver (client) implementation, highlighting its support for IPv6. This part concludes the implementation description of the getaddrinfo()library function as a continuation of Chapter 7 of IPv6 Core Protocols Implementation. Together, these two chapters will provide a comprehensive view of the complicated library. The latter half of this chapter talks about BIND, the...
