From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 11657 invoked from network); 26 Oct 2021 08:07:34 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 26 Oct 2021 08:07:34 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id A31919D0AE; Tue, 26 Oct 2021 18:07:31 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id CF5319CBF6; Tue, 26 Oct 2021 18:06:52 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=planet.nl header.i=@planet.nl header.b="ykVGKRi4"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 150759CBF6; Tue, 26 Oct 2021 18:06:48 +1000 (AEST) Received: from ewsoutbound.kpnmail.nl (ewsoutbound.kpnmail.nl [195.121.94.186]) by minnie.tuhs.org (Postfix) with ESMTPS id 6C6BE9CBED for ; Tue, 26 Oct 2021 18:06:42 +1000 (AEST) X-KPN-MessageId: 9d27e5af-3633-11ec-922e-00505699b430 Received: from smtp.kpnmail.nl (unknown [10.31.155.5]) by ewsoutbound.so.kpn.org (Halon) with ESMTPS id 9d27e5af-3633-11ec-922e-00505699b430; Tue, 26 Oct 2021 10:06:24 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=planet.nl; s=planet01; h=to:date:message-id:subject:mime-version:content-type:from; bh=xhU6V+6E0surS/lsQzu9FlvM5lx21vuHslaT7fvhfJs=; b=ykVGKRi4B82mayYnA+p7xJ1UAcLq3UTdm1K+/lVDJImZGDZG7ua8sTnm+2xGRXuuHoioqm7gp4uYq Q5i9Ocz2jPoGs+moVRm42jazzFoSqE3CN9hflwIcInmvPR9s15QRB3bEWaFH3Xw8ASF/KCwh6o36V0 XqNZAZpkoV64iRHE= X-KPN-MID: 33|Z6m0DznCRXfCKcHbhvkcEMxvf8mSSvvxoNKRe3t5C7I4DH/BT2XbE0xwPM39cjx QhM1c2qV939/LPDOUuFtxUta3V1BTLzIcnklipUjllvE= X-KPN-VerifiedSender: Yes X-CMASSUN: 33|Ha/YoljoAL5jIQKqbESLGQ9AujsnJpEqsVFV1wbWF8+uqjCkkOxOpIaFnv3ceWK DGoaCbf77LG7jcytn0Phn/Q== X-Originating-IP: 80.101.112.122 Received: from mba2.fritz.box (sqlite.xs4all.nl [80.101.112.122]) by smtp.kpnmail.nl (Halon) with ESMTPSA id a0ca89a3-3633-11ec-8d65-00505699b758; Tue, 26 Oct 2021 10:06:31 +0200 (CEST) From: Paul Ruizendaal Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.4\)) Message-Id: <4DB625DE-D35C-4734-9384-5785E54AC856@planet.nl> Date: Tue, 26 Oct 2021 10:06:30 +0200 To: TUHS main list , Lars Brinkhoff X-Mailer: Apple Mail (2.3608.120.23.2.4) Subject: Re: [TUHS] Unix NCP protocol stack for ARPANET X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" Noel wrote: >> 2. Note that the BBN TCP worked over NCP as its primary transport. >=20 > Your terminology is confused. TCP _never_ ran 'on' NCP; they were > _alternative_ protocol stacks on top of IHP (on the ARPANET). No > AHHP, no NCP. Yes, of course you are right. I meant BBN TCP used *Arpanet* as its = primary transport and hence has drivers for the IMP interface hardware. Lars wrote: > Here's the rub. Some hosts may have jumped the TCP/IP gun ahead of = the > 1/1 1983 flag day. The host tables don't say. Could it be that all > those VAXen were running experimental TCP/IP in January 1982? =46rom Mike Muuss=E2=80=99 TCP digest mailing list and a mail = conversation with Vint Cerf a few years ago I understood the following. = =E2=80=9CFlag day=E2=80=9D wasn=E2=80=99t as black and white as we = remember it now. During 1982 there was a continuous push to move systems = to TCP, and over the year more and more systems became dual protocol = capable and later even TCP only. Because all TCP traffic used the same, = dedicated Arpanet link number, BBN=E2=80=99s network control team could = monitor the level of usage. =46rom memory, in the Summer of 1982 traffic = was about 50% TCP and by October 70%. Presumably it reached 80-90% by = the end of the year. During 1982 on 3 occasions, network control activated a feature in the = IMP=E2=80=99s that refused traffic on link #0, which NCP used to = negotiate a connection. This caused NCP applications to stop working. = Again from memory, the first outage was a few hours, the second one a = day and third one, late in 1982, for two days. This highlighted systems = that needed conversion and helped motivate higher ups to approve = conversion resources. It seems that making the switch often involved = upgrading PDP11 to VAX. =46rom what I can tell flag day went well, although there were issues = with mail gateways that lasted for several weeks. At the start of 1982 there was no (usable) VAX Unix TCP code that I am = aware of. There were several options for the PDP11, but of those I think = only the 3COM code worked well. Around March/April there was code from = BBN (see TUHS 4.1BSD) and from CSRG (4.1a BSD). A special build of PDP11 = 2.8BSD with TCP arrived somewhat later. My impression is that this was = still the state of play on flag day, with 4.1cBSD only arriving well = into 1983.=