APNIC returning 223/8 to IANA

Thu Mar 20 19:51:45 UTC 2003

> 	Its not quite that simple folks.  The reason this particular
> 	block is reserved has some real technical merit, while the 69/8
> 	muddle is strictly due to ISP negligence.
> 
> 	RFC 3330 got it wrong.  Anyone remember the "Martian List"
> 	from the 1970-1990's?  Trying to use the all-ones or all-zeros
> 	network for real traffic is not possible.  Pre CIDR it was
> 	not possible to use 192.0.0.0/24 or 192.0.255.0/24. (the same was
> 	true on -every- network boundary) With CIDR,
> 	those boundaries moved to 1.0.0.0/24 and 223.255.255.0/24
> 	e.g. only two reservered blocks instead of hundreds.  
> 
> 	Simply having someonechange a DB entry or create an RFC will 
> 	not affect the installed silicon base.  Won't work.   
> 	APNIC is on the moral highground here.  They received damaged 
> 	goods without notification. IANA needs better technical clue.
> 
> --bill

Unless I'm mistaken, there is no technical issue with using the
All-0's or All-1's classful networks. In fact, several of those networks
are in use.

0.0.0.0/8	"this" network (all-zeros A)
127.0.0.0/8	loopback network (all-ones A)
128.0.0.0/16	reserved but unused (all-zeros B)
191.255.0.0/16	reserved but unused (all-ones B)
192.0.0.0/24	reserved but unused (all-zeros C)
223.255.255.0/24	reserved but unused (all-ones C)

As with 0/8 and 127/8, the other 4 networks could certainly be
designated for some use, including "normal" end-users. This type of
end-user usage would even continue to work with old classful gear.