nanog mailing list archives

Re: APNIC returning 223/8 to IANA


From: <bdragon () gweep net>
Date: Thu, 20 Mar 2003 14:51:45 -0500 (EST)


      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.


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