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Re: 16 year old bug

> Non-contiguous masks can indeed be useful, albeit only in specialized
> topologies and networks.  I could have used them in a paper I
> published just 1.5 years ago.  The trouble is that they conflicted
> with the routing table definition necessary for CIDR, and CIDR was
> and is necessary for the survival of the Internet.

Hm?  Conflicted how?  The routing table structures in use in NetBSD,
past and present, seem to handle both CIDR and noncontiguous netmasks
just fine - provided, as people point out, you avoid ambiguous cases,
but that's inevitable unless and until you pick a rule to resolve the
ambiguities.  (It doesn't need to be standardized, at least not beyond
the boundary within which the noncontiguous netmasks are confined.)

After all, CIDR masks are just a special case of arbitrary-bitmask
masks; code to handle the latter correctly will necessarily handle the
former.  (Conversion between bitmask masks and CIDR-style lengths is,
or at least can be, just an interface issue.)

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