[ih] The netmask

[John Gilmore]

Andrew G. Malis via Internet-history <internet-history at elists.isoc.org> wrote:
> people realized that since CIDR bit-masks were always all ones from
> the left and all zeros from the right, they could be equivalently
> represented by an integer count of one bits, usually following a "/"
> character

The Wikipedia page on CIDR says that Phil Karn invented the CIDR
"/bitcount" notation in the 1980s, citing two NANOG messages from 2018
with the remembrances of Brian Kantor and Bill Simpson:

  https://seclists.org/nanog/2018/Dec/334
  https://seclists.org/nanog/2018/Dec/368

  https://en.wikipedia.org/wiki/Classless_Inter-Domain_Routing#CIDR_notation

There's more CIDR history in that NANOG thread, though this week's
thread has covered a lot of it.

	John