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SubjectRe: all zeroes/all ones used in host IP's...
MAH> using "0's" in IP addresses.  Nobody could categorically say
MAH> wether or not they are allowed or not including myself, so I
MAH> hunted down RFC 1123, and found the relevant section.

It's really 1122 :)

MAH> IP addresses are not permitted to have the value 0 or -1 for
MAH> any of the <Host-number>, <Network-number>, or <Subnet-
MHA> number> fields (except in the special cases listed above).
MAH> This implies that each of these fields will be at least two
MAH> bits long.

MAH> I interpret the above as meaning that it is not legal to have a
MAH> network like this:

MAH> 192.168.0.0/24 or 23.0.0.0/24

MAH> with hosts 192.168.0.1 through 192.168.0.254 or with hosts
MAH> 23.0.0.1 through 23.0.0.254.

Why? 192.168.0.0 is a C class address, so it has the network number
192.168.0 which is not 0. As 23.0 is not equal to 0. So they are
allowed.

--
Meelis Roos (mroos@tartu.cyber.ee)

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