What was a Token Ring network?
dfarq.homeip.net
dfarq.homeip.net
Never ever seen it in my life though. It was a big "WAS" even then.
The i386-i486 machines we had in middle school were on the Ethernet bus (I remember the BNC cable going along the classroom, with T-joints to the network cards).
IIRC Token Ring wasn't a thing in practice for 100Mbit speeds and beyond, and went the way of the dodo faster than DOS did.
Sometime I wonder if any of the old protocols have new merit because of some other advance.
Fast-forward to 2013, when my wife was giving birth to our daughter in one of their hospitals, and I noticed an unused type-1 token ring wall jack in our room right beside some occupied 8P8C (aka RJ-45) jacks.
In comparison to that, traditional ethernet (think concentric cabling and terminators) glitched often and one flaky part of a cable could ruin your day.
ARCNET was much slower in theory, but robust, fair and stable and did not totally die under load from a single client.
I've definitely never seen any old Thicknet networks in use, though I have seen Token Ring in active use semi-recently. I never learned anything about Token Ring other than I remember old CompTIA mentioning it existed.
I do have a fondness for seeing this old tech that was way out of my reach or just barely too old to encounter back in the day being used, it's so neat to learn about. ClabRetro on YouTube is one of my few "drop everything and watch a new video" creators.
And at my previous job, in a quite normal office, there was a wallplate labeled DEC with the weirdest jack I've ever seen. I couldn't visually identify it, and I thought I knew everything. 1.5" inches wide, with a plastic spring-loaded cover that came down from the top. Maybe only two conductors in it, not normal rj-style pins at all. I'd guess something Vax, but I thought those were always ethernet since the early 80s, and anything older still wouldn't likely have survived until 2025.
We'd never gone over it when I went to college in 2012 but come 2022, I found myself learning about it by pulling it out of the ceiling during a decluttering project.
Made some sense, though. Being a TV station, coaxial cable was probably very plentiful when it was installed. We saved a couple of the vampire clamps at the time just for laughs. I wonder if they're still in the office.
Exact same! My neighbors (still friends to this day) managed to put their hands on lots of used 10base2 network cards and coax cables / Ts and terminators from a company that closed shop.
So we put those cards in our PCs and created a LAN and we had a coax cable going from our bedrooms (my brother and I) to the neighbors' house. On the third floor! We contemplated using utility cables in the middle of the street to hook the neighbor across the street but decided it wasn't wise (we were teenagers so we still contemplated the idea). We also fancied the idea of drilling a hole between the two houses: my neighbor's father was fine with it and provided us with a really long drill but my parents didn't want to hear about it.
And we didn't have the proper dedicated BNC connectors crimp tool though (and had zero idea where to buy one and were too broke anyway), so we became masters at building coax cables with BNC connectors by using regular pliers.
Them little orcs and humans from Warcraft 2 would then transit through the coax cable from house to house (so around 1995).
Fun fact: each system had an IN and an OUT coax port, and the coax cable was about as thick as a thumb. If a system died, a small hardware box short circuited, tying the IN and OUT coaxes together. This kept the ring intact, but it would also make that segment of the network longer and there were strict distance limitations between nodes. If the distance got too big, the entire ring broke. Also, if any coax cable got damaged, that also lead to a ring break. Prime had a special diagnostic program they could use on multiple nodes to try to find ring breaks.
IEEE 802.4 token bus standard was withdrawn
polled buses with a master are pretty common when you don't mind the performance hit and central-point-of-failure. i believe cable networks work this way.
CAN isn't a polled bus, doesn't have a master, and doesn't impose a performance hit. However, on a bus network, every device on the bus is a single point of failure: if it starts jabbering, the network stops working.
Being able to handle a collision without needing the higher priority message to skip a single beat seemed like magic to me when I first learned about it
IBM POWER is another odd one. They are still going strong because their shit Just Works so anyone doing Serious Business just keeps using them. They have hot pluggable CPU and ram ffs! Compared to cloud computing they are tiny, but they aren't going anywhere anytime soon.
I don’t disbelieve the author here but anecdotally the only time I’ve worked with coax BNC plugs for networking is with TR. And it be never seen a TR network in the wild that wasn’t coax.
It’s interesting to read that other cable types existed for TR.
I faintly recall that some of the older systems used the 9pin connectors.
And the first home ethernet I set up was BNC.
That was just one long, shared transmission line that happened with RG-58 coax. Each end was terminated with a 50 Ohm resistor. There was no central brain-box or hub. All nodes were peers.
Nodes could be inserted on an existing run by bisecting the coax at any random point, terminating the bare ends with BNC male connectors, and plugging those into a BNC T connector which ultimately connected to a NIC. Doing this brought down the entire network segment in unison until it was reconnected.
In fact, any discontinuity in the transmission line brought down the entire network segment.
So when Bob in Accounting decides to move his PC to a different spot on his desk and breaks the transmission line? The network dips out completely, and without any good tools for a IT folks to pinpoint exactly where that break happened.
Fun times. (Except: It actually was kind of fun for homelab-type stuff when 10BASE-T twisted-pair networks were still kind of expensive. Adding more nodes just meant installing more connectors and maybe extending the line. Now we just add another magical non-blocking N-way $15 gigabit network switch wherever, or skip it all and use wifi.)
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I've never worked with Token Ring at all. If I ever even saw it in the wild, I did not recognize it as such.
I do remember the flame wars about it, though.
https://en.wikipedia.org/wiki/10BASE2
The "T" in 10BASE-T signifies "twisted pair", which isn't the coaxial in thinnet.
Corrected. Thanks!
Coax Ethernet with BNC connectors was absolutely the norm for LANs from the late 1980s to mid 1990s. Then, slowly, UTP took over, as 10base-2 was replaced by 10base-T, then 100base-T, then switches instead of hubs, then Gigabit Ethernet: 1000base-T.
I worked with Token Ring in the '80s and never ever even heard of a coax version. It was D9 connectors on the card to fat IBM connectors on the MAU, as pictured here:
https://en.wikipedia.org/wiki/Media_access_unit
I think you're switching TR and thinnet Ethernet in your head.
Token Ring was a networking alternative to Ethernet.
With Ethernet when a node wants to transmit it just does so, then backs off and retries if there was a collision (someone else trying to transmit at the same time).
Token Ring avoided collisions by passing a "permission to transmit" token from node to node in circular (ring) fashion.
Depends on the Ethernet variant. Older versions have collision detection as you describe. More recent versions are point-to-point full-duplex and thus collision free, with the outlier of 10base-T1S, which uses a virtual token ring for collision avoidance.
Essentially that was the same for Ethernet too, everything on the same leg needs to talk at the same speed, though IIRC a different speed device wouldn't take down everything, it would just cause a significant excess of collisions due to the out-of-sync cross-talk and not be able to talk to anything itself. It wasn't until switching hubs and full switches were around that you could mix speeds on the same leg (with a switching hub you'd actually have two legs, one at each speed, bridged, with a full switch you have a separate collision domain per port so can mix speeds quite freely).
In principle, token ring was faster than Ethernet (which was CSMA/CD in the day): the mathematics of token ring were exact and analytic, and, when solved, gave higher speeds and better reliability than Ethernet, the mathematics of which were so complex (think three-body-problem) that analytic solutions were available only for bounding equations, which resolved to slower than token ring.
In practice, Ethernet was much faster.
A classic "the model is not the territory" problem.
[1] https://www.youtube.com/watch?v=R18APaR7mTQ at 28:54.
If you want to see how Scott Adams has gone crazy, watch e.g. Behind the Bastards episode(s) on him:
Lot more details: https://en.wikipedia.org/wiki/Token_Ring
Every other network I worked on was ethernet, with the exception of one arcnet network. Which also worked really well, except it was very, very slow.
Low priority devices must stop transmitting in the window, and switches will interrupt any transmissions not allowed.
The cable was laying right under my desk. When I touched it with my feet, there would be a disconnect because the coax t-connector was not sitting firmly enough on the network card of my device. All unsafe work would be lost.
Fun times.
When I was an intern at Merck in the late 1990s, the networking team was switching over from Token Ring to Ethernet.
It was so much work that they were openly recruiting anyone who was an employee or intern to come in on a weekend and help out. They eventually offered to pay people extra and a couple of my intern buddies took up the offer.
That textbook was sort of system textbook which describes a lot of low level stuffs such as networking, hard disks and such.
IBM were still using them in 2004.
In fact, broadcast ethernet is essentially token ring, except instead of a token it just grabs the wire. Only one machine can grab the wire at a time. Switches hide that from most people.
No, 'broadcast ethernet' is not token ring. There is no token. It's not a ring. Switches do hide the details, but it's hiding collision domains, not token passing.
https://www.automatedlogic.com/en/media/AAR_CS-aug2023_tcm70...
Ethernet got its latest in 2022 and another is in the pipeline.
It didn't last. Gigabit Ethernet began popping up around the time of the dot-com bubble bursting. That was it for Token Ring.
The main reason Ethernet won the war was because it was cheaper.
He should have stopped there. That was it. And because it was cheaper, less complicated to build the chips, 'good enough' networking, a bunch of folks jumped on the bandwagon. And here we are.
If you had a 16 megabit network and brought up a system at 4 megabits, it took down the whole network.
Well, yes, everyone who has ever mentioned TR tells some variation of this. And if you left the terminator off of the coax ethernet, you brought the whole network down. But TR got smart MAUs and ethernet got UTP hubs around the same time and problem solved.
And hubs were a lot cheaper than smart MAUs. Sooo...
Ethernet was junk if you went with the cheapest options all around, but you could make it acceptable if you invested some of the savings in improved technology.
Just like TR. If you were deploying dirt cheap 8228s after 1990 or so, your network still sucked. You didn't do that.
But the other reason Ethernet won was because of scale.
Yes, there was a thing called 100Mb Token Ring. Someone might have even shipped some number of them. I never saw one in the wild, and I don't know anyone who claimed they had who didn't work for IBM or Madge (which, btw, wasn't an 'obscure' network company at the time and made more than just TR cards).
That's because basically everyone who did Token Ring (IBM most of all) had decided that you wanted to scale TR you were going to ATM (for a bunch of mostly political and marketing reasons). Which, unlike TR, was in reality a very bad idea, but that's another story.
I've never even heard anyone even suggest 128Mb Token Ring, and I suspect someones LLM is hallucinating. There was a gigabit Token Ring standard (IEEE 802.5v), but I feel pretty confident saying noone ever shipped it. Like I said...ATM was gonna be the future.
Ethernet used a 15-pin connector that looks quite a bit like a PC joystick connector. Token Ring used a 9-pin connector that looks like a 9-pin video connector or an Atari style joystick plug.
Ok...I'll just be snarky and point out there are ethernet cards that use a 9-pin D-sub connector to reuse a TR wiring physical plant. I have several.
Coax connectors for Token Ring did exist
Citation needed. I've seen coax for 802.4 industrial networking stuff, which is not TR. I'm betting more hallucinations.
ARCNET was another competitor from the same timeframe. It, too, was a contender for a while because it was backed by Datapoint, a pioneer in office automation using small computers.
Arcnet was a contender because it was even cheaper than ethernet and it was (and still is) widely used in industrial environments. And some popular early PC file sharing systems (e.g. LANTastic) would use Arcnet.
In 1970, Datapoint created a desktop computer, the Datapoint 2200, with an 8-bit TTL processor. Intel created a microprocessor version of this processor for Datapoint, called the Intel 8008. Datapoint decided to stick with TTL, so Intel ended up selling the 8008 as a general-purpose microprocessor. Intel improved it to make the 8080, then made a 16-bit version, the 8086, as a stopgap product until the iAPX 432 micro-mainframe was ready. The iAPX 432 was a disaster and that's how you ended up with x86.
I wish I had a smart mau but she is standing on the windowsill mau-ing at the part that doesn't open while the other side is wide open. In the rain. Which is getting inside while she maus to get inside.
Apollo Domain computers had a token ring which used coax. RCA phono plug connectors. We had a pair of those at the aerospace company for testing. Worked OK, but too weird. We ended up with Sun workstations.
At various times in my early career, I was involved with strange networking hardware only of historical interest now. Apollo Domain (sort of like Unix, but not.) "Thick Ethernet" 10BASE5. Later "Thin Ethernet" (Yes, you can mix thick and thin Ethernet without an impedance mismatch, but you may need to use a time domain reflectometer to check. The adapters were built to tolerate TDM pulses.) Hyperchannel, 20Mb/s which required 6U of rack space for the interface. (We had a pair, surplus from another project, but didn't do much with them.) DECNET triaxial cable for connecting things called the DMC-11.
These were all coax, and they were all true "baseband", that is, the signal was meaningful down to DC. No differential signals, and no scrambler to make the number of 1 and 0 bits roughly equal. You can't use decoupling capacitors or transformers. They were all susceptible to noise and ground loops. The coax shield should only be grounded at one point for the whole chain. Otherwise, noise in the ground comes through as noise in the cable. All this was no problem in a place full of RF engineers, who knew all that, and considered hooking up a TDR or a scope to a data network normal operational setup. And in an RF R&D facility, where copper busbars an inch wide were run in parallel with electrical ducts to solidly ground out noise, ground was solid.
So coax worked fine at Xerox PARC, it worked fine at Stanford (although inter-building coax didn't work all that well), it worked fine in single-room installations, and it worked fine for organizations which understood the limitations of non-differential baseband over coax. The coax technology thus needed too much basic electronics knowledge for general office use.
Modern Ethernet is pretty much idiot proof at the electrical level. It's differential signals over a pair, immune to common-mode noise and ground level differences. If you plug standard cables into standard interfaces, it will work.
Which is why coax Ethernet went away.
We just had two loaners for a demo, so we might have been given an old model. We were evaluating workstations, and had various devices for a few months at a time.
I saw quite a bit of rare early hardware over my career. Much of it was rare for a good reason.
I saw quite a bit of rare early hardware over my career. Much of it was rare for a good reason.
Indeed. We should swap stories over a beer some time.