Re: v6ops-v6onbydefault: link-locals and AI_ADDRCONFIG

[Pekka Savola <pekkas@netcore.fi>]

Two points to clarify..

On Wed, 29 Oct 2003 itojun@iijlab.net wrote:
> >IMHO, without the on-link assumption, AI_ADDRCONFIG could help a lot in
> >dual-stack deployments where IPv6 connectivity is not yet enabled.  
> 
> 	could you clarify what you meant by "dual-stack deployment"? [...]
> 	if it means "dual-stack host in IPv4-only network", it can live fine
> 	without AI_ADDRCONFIG.

Yes, I mean the above.  AI_ADDRCONFIG makes one avoid completely 
unnecessary AAAA DNS lookups in the case that the addresses are not useful 
in any case.

> > - there are really misbehaving DNS servers out there, which jeopardize 
> >your IPv4 service if you query for AAAA's, and
> 
> 	this is a separate problem (this is not what AI_ADDRCONFIG cares
> about).

Yes, this is a separate problem .. but one that AI_ADDRCONFIG works around
for the vast majority of nodes which could be dual-stack, but without IPv6
connectivity.  So, in that sense, IMHO AI_ADDRCONFIG helps the situation
*a lot*, but of course we still have to fix the problem for those 
dual-stack nodes that do, in fact, have IPv6 connectivity.

Remember, the most important thing we should care about is that dual-stack 
deployments can get more common without causing problems for *IPv4* or 
services in general.  AI_ADDRCONFIG is one step in that direction.

-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings