1 DNSOPS / Vienna IETF / July 2003 / Bob Hinden IPv6 DNS Discovery, and why it is important Bob Hinden

2 DNSOPS / Vienna IETF / July 2003 / Bob Hinden IPv6 AUTOCONFIGURATION IPv6 Neighbor Discovery and Stateless Auto-Configuration Defined in RFC2461 and RFC2462 Provide the ability to Learn Prefixes, Link Information (MTU, etc.), Routers, Resolve addresses, etc. Create Unicast Addresses Everything to become a functional IPv6 node, except: –Resolve Names

3 DNSOPS / Vienna IETF / July 2003 / Bob Hinden IS THIS A PROBLEM? An IPv6 node that can’t resolve names isn’t very useful Can’t use URLs, host names, etc. IPv6 Addresses are difficult to type by people –1080:0:0:0:8:800:200C:417A Name resolution is a basic IP service They even provide a basic form of service discovery ftp.ietf.org, ntp.ietf.org, ….

4 DNSOPS / Vienna IETF / July 2003 / Bob Hinden MISSING FEATURE The lack of the ability to resolve names is a missing feature of IPv6 Stateless Autoconfiguration Hasn’t been a big problem in the past, because Most AAAA records have been retrieved via IPv4 Native IPv6 DNS is now being deployed Solution is needed soon Lack will slow down IPv6 deployment Discourage non-standard solutions

5 DNSOPS / Vienna IETF / July 2003 / Bob Hinden WHAT IS NEEDED Main requirement Learn the address of one or more IPv6 Recursive DNS servers –Lifetimes (?) Nice but not required Default domain (DNS suffix) Default search list Other? Non-Requirements General service discovery solution

6 DNSOPS / Vienna IETF / July 2003 / Bob Hinden SOLUTION SPACES Create Neighbor Discovery Router Advertisement Option Simple, gives router administrator control Router likely has information anyway Finishes IPv6 Autoconfiguration Create well known addresses for IPv6 DNS Resolvers Like old approach Could use new Local Addresses or Global Addresses

7 DNSOPS / Vienna IETF / July 2003 / Bob Hinden WHY NOT DHCPv6 Overkill if only DNS Recursive Server information needed and DHCP isn’t being used for address assignment Stateless DNS? IPv6 Autoconfiguration works better than DHCPv4 in dynamic environments IETF meetings are a good example Practical problems DHCP RFC isn’t out yet Little experience

8 DNSOPS / Vienna IETF / July 2003 / Bob Hinden SUMMARY The ability to resolve names is missing from IPv6 Autoconfiguration IPv6 Nodes are not very useful if they can’t resolve names Standard solution needed soon