RFC 962

TCP-4 Prime 🎀

okay bestie, the title block first 💖 This is RFC 962, called "TCP-4 Prime," written by M. A. Padlipsky from Mitre-Bedford in November 1985 🌸 It's a Network Working Group doc, and it does not propose a standard. The title block doesn't list anything it obsoletes or updates ✨

STATUS OF THIS MEMO ✨

okay so this memo keeps the chat going about a possible transaction oriented transport protocol 🦋 It is not proposing a standard, and distribution is unlimited, so share it with whoever 💅

DISCUSSION 💜

so Bob Braden put out a call for a transaction oriented protocol in RFC-955, and these thoughts came to mind 🧚

• The perceived problem is that connection set-up and tear-down take too long. 🥲
• Other parts of TCP's reliability and robustness approach are presumably still desirable. 🫶
• We have some spare command bits in the TCP header, and I trust that there's still a version number field. 🤞
• So why not add NYS (no-way handshake) and NIF (graceless close) commands to TCP and leave everything else as was (except for the version, of course)? 🔥

ngl, that might be a little at odds with "the spirit of TCP," but pragmatically it ought to do the trick 💅 Some careful crafting might be required for ISN handling with NYS. My guess is that if you have to resend the first, possibly only, segment, you just pretend you're all of a sudden in the middle of SN space (initially you start at the bottom of it) 🌈 When it sees the funny ISN, the NYS handler knows it should dequeue anything it might have had pending for (re)transmission and start fresh. It assumes that if anything gets through to the starting side belatedly, it'll get chucked because it's well outside the left edge of the window, if I'm remembering that part right 🙈

and please be aware that I'm not bothering to confirm recollections, because I don't want to pretend this is the spec. It's just meant to be the concept, in TV talk 📺✨

(On the NYS emitting side, presumably you just drop right into ack_expected state, or whatever the right name is, after setting an appropriate bit that'll get you to fiddle the ISN if you take a timeout.) Maybe you even fiddle the ISNs more elaborately, to allow for several false starts rather than "two strikes and you're out." Maybe we take some spurious segment hits if SNs get suitably balled up 💀 But if you really think handshaking is too expensive, then that's the way the premise crumbles 😭

Speaking of graceless closes RFC>>> 🌙

RFC 962 November 1985 TCP-4 Prime