On Tue, May 29, 2007 at 02:06:54PM +0200, Iljitsch van Beijnum wrote:
DHCPv6 can't provide a default gateway, you need stateless autoconfig for that even if you use DHCPv6 for address assignment.
I think you mean "router advertisement", not stateless autoconfig. You don't need the M bit clear in order to use the router. On this topic, DHCPv6 also can't deliver a subnet prefix to clients. These are only delivered by router advertisements containing prefix options (not all router advertisements will contain prefix options, or may not include a prefix covering the allocated address), and without them, DHCPv6 implementations are justified in assuming the allocated address is a /128. Logically, they can't talk to one another without an advertising router present. So...I think how these two protocols comingle could use some work. In truth, I think we should just ditch rtadv/rtsol and add routers and subnet-mask options to DHCPv6. That's a shorter path with more finality than the pandora's box of adding options to rtadv.
And there is the extra info, but DNS resolvers may be availalbe in stateless autoconfig in the future as well.
Again, you mean in rtadv. Is it just me, or does it seem unusual for network infrastructure to advertise host configuration parameters? Maybe I'm getting old, but the idea of managing this configuration information in my routers sounds like a real chore compared to the old DHCP relayed central server model.
This is probably the way we want to do IPv6 address provisioning for end-users in the future, but that requires that home gateways that implement IPv6 routing functionality come with the DHCPv6 prefix delegation client capability and have this configured by default so it all works out of the box.
There's also a bit of a hinky issue in routing the delegated prefix to the client. Obviously, you don't trust route advertisements from the client - you're not going to run OSPF or BGP with all your broadband customers. How to "do this" in a way we can all just plug and play hasn't quite been decided yet. Would there be interest on a DHCPv6 related presentation at NANOG? -- David W. Hankins "If you don't do it right the first time, Software Engineer you'll just have to do it again." Internet Systems Consortium, Inc. -- Jack T. Hankins