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Re: 16 year old bug

>> I wouldn't say _nothing_.  See below.
> That's why I said "essentially nothing" - for your two /29's, you
> must have had a max of 14 hosts.   You could have renumbered those in
> less than half an hour, even if you had to manually do it to every
> one.

Well, there were external pointers to at least a few of those
addresses.  Fixing even just the ones I knew about would have been
nontrivial.  Indeed, that was one of the most sigificant aspects of
switching away from that address space when I finally did; fortunately,
I had the opportunity to run the old and new space in parallel on the
same broadcast domain for a substantial time, making it much less pain
to switch the external pointers.

> That is, implementations are free to to whatever they like (these
> days) if you use non-contig masks.

Sure; it's a quality-of-implementation issue, same as, say, accepting
only (in today's terminology) mask widths that are multiples of 8 bits.
And yes, I ran into some such implementations back in the '80s; even
then, we considered them annoyingly broken, much as I'd consider an
implementation that misbehaved in the presence of noncontiguous masks.
Or one that couldn't be configured to obey source routes.  Or any of
endless other issues.

I recall talking with someone, once, who was involved in interop
testing back in the '80s/'90s, before support for masks other than /8,
/16, and /24 became "universal".  The tale as I remember it was that
he'd tell vendors that "the mask on the show floor network is", with them looking worried; when feeling evil, he'd then
tell them "and next year it'll be", followed by their
(figuratively) running screaming, with a speed dependent on their
ability to convert decimal to binary.  (I don't know how much truth
there is in it; I suspect they never actually did that.  Pity.)

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