11.1 INTRODUCTION

In this chapter we will look at the changes which are required to make the Domain Name System support hosts operating IPv6. These changes incorporate a new resource record type to record an IPv6 address, a new domain to support lookups founded on an IPv6 address, and revised definitions of existing query types that return Internet addresses as a component of additional section processing. The extensions are intended to be compatible with existing applications as well as DNS implementations.

11.2 DNS EXTENSIONS

Existing support for Internet address storage in the Domain Name System (DNS) is not expanded to support IPv6 addresses. This is due to the fact that applications presume that address queries only return 32-bit IPv4 addresses.

To support IPv6 address storage, it is necessary to designate extensions such as a new resource record type which is defined to map a domain name to an IPv6 address. Also, a new domain is designated to support lookups based on these addresses.

In addition, Present queries which execute additional section processing to find IPv4 addresses are designated to execute further section processing on both IPv4 and IPv6 addresses. These alterations are intended to be compatible with existing software. The present support for IPv4 addresses is maintained.

11.3 RESOURCE RECORDS

New record types are defined to record a host's IPv6 address, and a host that has greater than one IPv6 address needs to have greater than one such record. The AAAA resource record type is a new record distinct...