2008.02.20 NANOG 42 IPv4 PTR queries for unallocated space

Thu Feb 21 10:43:00 UTC 2008

On 21 feb 2008, at 11:07, Joseph Jackson wrote:

> How come RFC 1918 addresses aren't real enough?

Because they look like RFC 1918 addresses.

On 21 feb 2008, at 11:30, Andy Davidson wrote:

>> For instance, I do a training course where people need to configure  
>> routers, and I use addresses out of 96.0.0.0/8 for that, because it  
>> has to be clear that we're talking about real addresses and not RFC  
>> 1918 stuff.

> Do you think you could consider some of the rfc3330 ranges like TEST- 
> NET - 192.0.2.0/24 - or if you need more than one network,  
> 191.255.0.0/16 ?

Nothing is impossible, but shoehorning stuff into a small range  
doesn't make for a realistic training setup.

>> Would it be useful for IANA to publish the order in which they're  
>> going to allocate /8s? That way, it's easier for people to plan  
>> getting out of the way of real deployment in time.

> Well it's a pretty safe bet that most of today's unused /8s will be  
> allocated within the next couple of years !

That's true. (Well, it's more like three years: there are currently  
41 /8s available and last year, 14 were allocated to the RIRs.)

I guess that means that people who want to use "off-label" address  
space should probably use the legacy /8s that are assigned but don't  
show up in the routing table.