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=-1.0 required=5.0 tests=MAILING_LIST_MULTI, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 22127 invoked from network); 26 Jun 2022 09:48:09 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 26 Jun 2022 09:48:09 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id F0E8A4097F; Sun, 26 Jun 2022 19:47:30 +1000 (AEST) Received: from pasta.tip.net.au (pasta.tip.net.au [203.10.76.2]) by minnie.tuhs.org (Postfix) with ESMTPS id A04584097D for ; Sun, 26 Jun 2022 19:47:16 +1000 (AEST) Received: from [192.168.1.2] (219-90-181-104.ip.adam.com.au [219.90.181.104]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pasta.tip.net.au (Postfix) with ESMTPSA id 4LW5bl284kz8swF; Sun, 26 Jun 2022 19:46:42 +1000 (AEST) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.21\)) From: steve jenkin In-Reply-To: <20220626021956.0140918C0A2@mercury.lcs.mit.edu> Date: Sun, 26 Jun 2022 19:46:40 +1000 Content-Transfer-Encoding: quoted-printable Message-Id: <1C6AFC69-F616-421A-B7BA-376ACDC295BA@canb.auug.org.au> References: <20220626021956.0140918C0A2@mercury.lcs.mit.edu> To: TUHS X-Mailer: Apple Mail (2.3445.104.21) Message-ID-Hash: FUHNKCMU2SPIW636J45MA7QZENQ7P6JM X-Message-ID-Hash: FUHNKCMU2SPIW636J45MA7QZENQ7P6JM X-MailFrom: sjenkin@canb.auug.org.au 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 CC: Noel Chiappa X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: Research Datakit notes List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: > On 26 Jun 2022, at 12:19, Noel Chiappa = wrote: >=20 >> From: Paul Ruizendaal >=20 >> it would seem to me that Sandy had figured out a core problem some 30 >> years before the TCP/IP world would come up with a similar solution. = I >> would not even be surprised if I learned that modern telco routers >> transparantly set up virtual circuits for tcp traffic. >=20 > To fully explore this topic would take a book, which I don't have the = energy > to write, and nobody would bother to read, but...=20 packet switching won over Virtual Circuits in the now distant past but in small, local and un-congested networks without reliability = constraints, any solution can look good. If =E2=80=9CPerformance is Hard=E2=80=9D, so = are Manageability & Reliability. Packet switching hasn=E2=80=99t scaled well to Global size, at least = IMHO. Ethernet only became a viable LAN technology with advent of Twisted = pair: point to point + Switches. The One Big Idea for common channels, collision detection/avoidance,=20 became moot, even irrelevant with switch buffering & = collision-less connectivity. Watching networking types deal with ethernet multi-path routing & link = failover - quite problematic for 802.1 layer-2 nets, I can=E2=80=99t but think =E2=80=9CIf you don=E2=80=99t design a feature = in, why expect it to show up?=E2=80=9D. All those voluminous CCITT / ITU-T standards were solving the problem = =E2=80=9Ckeep the network up & working=E2=80=9D, they knew it wasn=E2=80=99t easy =E2=80=98at scale=E2=80=99. Harder if = you have to billing :) Something I=E2=80=99ve never understood is how to design large-scale VM = farms , where DB=E2=80=99s, Filestores & =E2=80=99services=E2=80=99 (eg Web) = have to be migrated between physical hosts, made more difficult when services have to be split out of existing = instances: who gets to keep the MAC & IP address? I can=E2=80=99t see either a layer-2 or IP addressing scheme that=E2=80=99= s simple and works well / reliably for large VM fleets. Whereas, =E2=80=98well known=E2=80=99 Virtual Circuit endpoints can be = permanently allocated & tied to an instance/service. Packet encapsulation & separation techniques, like MPLS, VPN=E2=80=99s = and VLAN=E2=80=99s, are now commonplace in IP networks. Even the ubiquitous (multi-level) use of NAT for traffic isolation & = preventing unwanted ingress shows, IMO, a design failure. Why would I advertise my internal network with IPv6 and allow every bad = actor to probe my entire network? Hellish security admin for little = benefit. I=E2=80=99ve never understood this reasoning. It seems to me, IP networks are trying to provide the functionality of = Virtual Circuits - dedicated paths, transparent failover & even = committed data rates. There are two very valuable functions that =E2=80=98dedicated paths=E2=80=99= , implying topology-aware switches, can do that packet-switch can=E2=80=99= t: - Network-based =E2=80=9CCall Transfer=E2=80=9D There=E2=80=99s no packet-switch mechanism I know, that allows a connection to an advertised =E2=80=98gateway= =E2=80=99 or authenticator, that then allows invisible network rerouting of the = connection to a =E2=80=99service provider=E2=80=99 or host, without giving away information to the caller. This would be really handy for =E2=80=9Cfollow me=E2=80=9D= connections, moving between user devices, even different access = networks. Apple have just announced something like this - moving = running sessions between Mac, iPad, iPhone as needed. The inverse, =E2=80=9Cblocked caller id=E2=80=9D, = can=E2=80=99t be done in IP without a repeating host, ence VPN=E2=80=99s. [ In telephony, all A & B parties are identified for = billing & forensics / interception. Addrs only hidden from other users. = ] - =E2=80=9CMulticast=E2=80=9D / Conference calls Packet switched =E2=80=98conferencing=E2=80=99 is rarely = done by the Network, despite multicast IP standards 25yrs of more old, = they are rarely used. If major router vendors had good solutions, they=E2=80=99d= be pushing them. The Pandemic brought forward the need for video calling = everywhere, created a market for =E2=80=9CConferencing=E2=80=9D products = & =E2=80=9CStreaming=E2=80=9D. Isn=E2=80=99t Multicast of Free To Air TV & radio over = Internet both obvious & desirable? It should be the modern equivalent of & replacement for = =E2=80=98wireless=E2=80=99 broadcasting. Should be trivial if everyone has one or more mobile = devices and a home Internet connection. The current Point-Point transmission model of Streaming = Services - no scheduled broadcasts, On-demand only - seems to be the most resource intensive, hence = costly, solution possible. Flash storage is under $0.20/GB, a small PVR with 1TB of = =E2=80=9Ccircular buffer=E2=80=9D could cheaply convert =E2=80=9CScheduled= =E2=80=9D to =E2=80=9COn Demand=E2=80=9D at the customer premises. [ Samsung have announced a 1.5TB micro-SD card, targeted = at surveillance recording. Purportedly, =E2=80=9C100 days of video=E2=80=9D= . Cost? NFI ] One of the modern challenges for Enterprise Customers is =E2=80=9Cchange = network provider=E2=80=9D. One major Aussie firm just took two years to move Service Provider and = it was =E2=80=99news=E2=80=99. 25yrs ago, and probably now as well, interconnecting / splitting = corporate networks following merges / de-merges was a huge task. IP networks require re-numbering and basic IP services, like DNS, email, = web, need re-provisioning / re-platforming. The Worst Case error - happens too often - is Network Admins cutting = themselves off from the Remote Admin Network. =E2=80=98Recovery=E2=80=99 is slow & painful - all sites / all devices = may have to be visited, even if you have a backup network link. Did Microsoft have a fault like this in the last 12 mths after it = acquired a vendor? There was a big outage. Post merger, Enterprise phone switch & voice network are relatively = simple & fast to change and rarely result in Admins losing Remote Admin = access. It=E2=80=99s not that I don=E2=80=99t like cheap, easy Ethernet devices = that mostly Just Work and at small scale are simple to setup and easy to = manage. 30 years of hardware development has been a boon to us all, in almost = all ways. Rob Pike wrote a great piece (in the 1980=E2=80=99s) about cheap = hardware forcing systems software to take up the slack, an example I = thought of Ashby=E2=80=99s Law of Requite Variety. Have we arrived in this Packet Switch nightmare because of "Microsoft is = Best=E2=80=9D thinking? I don=E2=80=99t have a proper name for this blinkered view of the world, = backed by arrogance & the assumption =E2=80=9CWhat I don=E2=80=99t know = can=E2=80=99t matter=E2=80=9D. regards steve j -- Steve Jenkin, IT Systems and Design=20 0412 786 915 (+61 412 786 915) PO Box 38, Kippax ACT 2615, AUSTRALIA mailto:sjenkin@canb.auug.org.au http://members.tip.net.au/~sjenkin