On Thu, Jan 18, 2018 at 10:39 AM, Grant Taylor via cctalk < cctalk@classiccmp.org> wrote:
> I was not aware that there was code that supported /only/ Class A (/8) > addresses and /not/ Class B (/16) or Class C (/24) addresses. > > I /thought/ that everything was either classful (as in supports all three > classes: A, B, and C) or classless (as in supports CIDR). > Years ago I added a configurable "bozo-arp" feature to the Telebit NetBlazer router, which would respond to ARP requests for non-local addresses and reply with the router's MAC address (on that interface), specifically in order to make classful-only hosts work on a CIDR network. Later someone paid me to write a NetBSD daemon ("anyipd") to do the same thing, though for an entirely different reason. Recently I've needed that functionality on Linux, as I have multiple old systems that only understand classful, including the AT&T UnixPC (7300 or 3B1). I suppose I should rewrite and open-source it.