v4 given v6

[bmanning@ISI.EDU]

> 
> > Given a 6bone node's v6 address, what's the best way to find a v4 address
> > for the node (if it has one)?
> 
> I would look up the PTR record in ip6.int, then look up the A record
> for that name.  However, there are some obstacles:
> 
> 	The ip6.int is often not well-maintained.  We knew about this
> 	problem from the git-go.
> 
> 	Some people are naming their IPv6 nodes in a separate
> 	subdomain, maybe because their regular DNS servers don't
> 	support AAAA records.

Hum..

ip6.int

total zones	successful	no-zone	other  %accurate
252		149		103	0	59.1%

e.f.f.3.ip6.int. only

total zones     successful      no-zone other  %accurate
139		92		47	0	66.1%

For the e.f.f.3.ip6.int. tree, of the no-zone failures,
	
total 	  firewalled
failures  refused 	no server	other
47	  26		18		3

Compare that with the last data on the IPv4 inverse tree of
just over 57% accurate.

I need to go off and compare the IPM stats vs Tony Bates 
prefix lists and get a stability metric for the routing
system.  I expect it is close.  To paraphrase your statement Matt,
I would say, "The routing system is often not well-maintained.
We knew about this problem from the git-go."

--bill