Email delivery protocols / methods.

-----Original Message----- From: cctalk <cctalk-bounces at classiccmp.org> On Behalf Of Grant Taylor via cctalk Sent: 05 July 2019 22:06 To: cctalk <cctalk at classiccmp.org> Subject: Email delivery protocols / methods. Here's pot stirrer for a holiday Friday afternoon: How many different protocols / methods can we collectively come up with for how email can be transferred? I'm primarily thinking about between servers (MTA-to-MTA). But I'm also willing to accept servers and clients (MTA-to-MUA). Where you can / could run at least one server yourself. ? SMTP(S) ? UUCP (rmail) ? MMDF ? X.400 ? Microsoft Exchange proprietary protocol ? Novell GroupWise proprietary protocol ? Lotus (IBM) Domino proprietary protocol ? FidoNet (FTN) ? BITNET ? Direct file access - group Post Office ? Direct file access - mail spool -- Grant. . . . unix || die