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=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 17004 invoked from network); 24 Jun 2022 06:47:54 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 24 Jun 2022 06:47:54 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id D734F4094A; Fri, 24 Jun 2022 16:47:30 +1000 (AEST) Received: from ewsoutbound.kpnmail.nl (unknown [195.121.94.170]) by minnie.tuhs.org (Postfix) with ESMTPS id CF9DC40947 for ; Fri, 24 Jun 2022 16:47:12 +1000 (AEST) X-KPN-MessageId: 6d6a5f3a-f389-11ec-8294-005056ab378f Received: from smtp.kpnmail.nl (unknown [10.31.155.38]) by ewsoutbound.so.kpn.org (Halon) with ESMTPS id 6d6a5f3a-f389-11ec-8294-005056ab378f; Fri, 24 Jun 2022 08:46:51 +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=EJ+7Nn61az3UOab52YRnHjLu8r+YcLKEBfR6pvuGZuQ=; b=N7eCneAVNFMjNuOeZd9wmPVVchO8O1zI8OLGY8o7AajPb2Z/tS9k2eAETjKtH4hYsmlDgbdJq4YRK 6/3SYH0Csvn9UXtTNtX9DZcvjh98cmxg3Qqtm8o6taENCVzKuytf6195JK3pgwXdOpoBAsNw4FaFbP SkYkL8ZECdeblZS8= X-KPN-MID: 33|ptOB5Od1Pfy0kbjyLk8d7LeGP8HbgwlcRqM4CFry8p8hucvDDAbYJs9tPGOhnR0 jsSzovw/0etdOAB1Dj+eeVtYkVj7Xjv7oJ7yPKjBJs5I= X-KPN-VerifiedSender: Yes X-CMASSUN: 33|yrmz9pWtbYTJJYYGBS70Du7Rpr1sHwcSxvFzmkswgBLvD9dF4U7bxWUCi3YPeRs mkC7vWObBz0O+qEDEq/sGvg== X-Originating-IP: 77.172.38.96 Received: from smtpclient.apple (77-172-38-96.fixed.kpn.net [77.172.38.96]) by smtp.kpnmail.nl (Halon) with ESMTPSA id 730445bd-f389-11ec-b5e4-005056abf0db; Fri, 24 Jun 2022 08:47:00 +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 14.0 \(3654.120.0.1.13\)) Message-Id: <38ED67E4-4D75-47A8-BA44-4A08DF487EC2@planet.nl> Date: Fri, 24 Jun 2022 08:47:00 +0200 To: tuhs@tuhs.org X-Mailer: Apple Mail (2.3654.120.0.1.13) Message-ID-Hash: E3TJTBPXSAUO6C6YLJXYO2SLTZE4S4KR X-Message-ID-Hash: E3TJTBPXSAUO6C6YLJXYO2SLTZE4S4KR X-MailFrom: pnr@planet.nl X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-tuhs.tuhs.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: forgotten versions List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Tue, Jun 21, 2022 at 05:56:02PM -0600, Jacob Moody wrote: > I recently stumbled across the existence of datakit > when going through the plan9foundation source archives. > Would be curious to hear more about its involvement > with plan9. There are at least 2 versions of Datakit. I my current understanding = there are =E2=80=9CDatakit=E2=80=9D which is the research version, and = =E2=80=9CDatakit II=E2=80=9D which seems to be the version that was = broadly deployed into the AT&T network in the late 80=E2=80=99s -- but = very likely the story is more complicated than that. Plan9 is = contemporaneous with Datakit II. In short, Sandy Fraser developed the =E2=80=9CSpider=E2=80=9D network in = 1970-1974 and this was actively used with early Unix (at least V4, maybe = earlier). Sandy was dissatisfied with Spider and used its learnings to = start again. The key ideas seem to have gelled together around 1977 with = the first switches being available in 1979 or so. The first deployment = into the Bell system was around 1982 (initially connecting a handful of = Bell sites). In 1979/1980 there were two Datakit switches, one in the office of Greg = Chesson who was writing the first iteration of its control software, and = one in the office/lab of Gottfried Luderer et al., who used it to = develop a distributed Unix. Datakit at this time is well described in two papers that the ACM = recently moved from behind its paywall: https://dl.acm.org/doi/pdf/10.1145/1013879.802670 (mostly about 1980 = Datakit) https://dl.acm.org/doi/pdf/10.1145/800216.806604 (mostly about = distributed Unix) The Chesson control software was replaced by new code written by Lee = McMahon around 1981 (note: this is still Datakit 1). The Datakit driver = code in V8 is designed to work with this revised Datakit. Three aspects = of Datakit show through in the design the V8-V10 networking code: - a separation in control words and data words (this e.g. comes back in = =E2=80=98streams') - it works with virtual circuits; a connection is expensive to set up = (=E2=80=98dial=E2=80=99), but cheap to use - it does not guarantee reliable packet delivery, but it does guarantee = in-order delivery Probably you will see echoes of this in early Plan9 network code, but I = have not studied that.