On Wednesday, August 10, 2022 04:12:11 AM Curt wrote: > I never realized that local addresses were fundamentally identical in all > local networks because there weren't enough addresses in the first > place, and that NAT was essentially designed to palliate this shortage.
Yes, aiui, NAT was designed because of the address shortage, but ... > I thought the latter was some sort of security measure. at least in early versions of NAT (more below) it also provided some level of security as it was designed to only forward incoming connections (to computers in a LAN) from "known" external computers. I.e., if a computer on the LAN contacted a computer outside the LAN, NAT would allow incoming data from that external computer, but not allow incoming data from other external computers. I'm not sure that current implementations of NAT provide that same functionality, (but it is sort of a natural thing -- if something comes in from an unrecognized external computer, it would not know which computer (on the LAN) to forward it to, so it would presumably just be dropped. Background: My first encounters with NAT were back in the days (pre-2020) when my LAN consisted only of DOS (or Windows) computers. One (DOS) computer on the LAN ran one or more software packages that (1) interfaced to the dial-up (!!) modem and (2) provided the NAT functionality. I don't recall if that was one package or two, and in any case, I don't recall the package name(s). -- rhk If you reply: snip, snip, and snip again; leave attributions; avoid HTML; avoid top posting; and keep it "on list". (Oxford comma included at no charge.) If you change topics, change the Subject: line. Writing is often meant for others to read (legal agreements excepted?) -- make it easier for your reader by various means, including liberal use of whitespace. If someone else has already responded to a question, decide whether any response you add will be helpful or not ... A picture is worth a thousand words -- divide by 10 for each minute of video (or audio) or create a transcript and edit it to 10% of the original.
