nanog mailing list archives

Re: test Nets being routed?


From: "Howard C. Berkowitz" <hcb () clark net>
Date: Tue, 23 Dec 1997 20:14:37 -0500


permits/denys what?  (a retorical query)
the point being that there is no practical difference btween

      199.2.98.0/24
and    192.0.0.0/24
or     128.0.0.0/24
or     191.255.255.0/24

these prefixes (and delegation points) are valid or potentially valid
in the routing system whereas

      192.0.2.0/24
and    172.16.0.0/16
and    192.168.0.0/24
and    10.0.0.0/8

are not.

--bill (off to re-read RFC 1519 and RFC 1918 just to make sure)

Bill,

You remind me of something I've been hunting for, which I think is relevant
to a lot of operationally related educational examples.  Are there prefixes
that are likely to stay unassigned for the moderate to long term, other
than the RFC1918 group?

If I'm showing how to use a NAT with private address space on one side and
registered space on the other, I'd like to use some "safe" prefixes on the
public side that are NOT from RFC1918.  Is there some block likely to stay
with IANA?  Or possibly some space assigned to the military and likely to
stay in a secure network?

I really feel for the people who have 202.222.5.0, 131.108.0.0, and the
other prefixes used in Cisco educational material for many years!  How many
clueless people have picked those as their network numbers?

Howard





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