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Celebrating The Origins of Packet Switching

XaN-ASMoDi writes with an interesting historical piece at the BBC on the early history of packet switching, excerpting: "It has often been said that change is the only constant in the 21st Century. And there is little doubt that the restless tone of these times is something that the web has helped to accelerate, but the only reason that [...] the web can cope with that punishing pace is thanks to work done four decades ago by British mathematician Donald Davies at the UK's National Physical Laboratory (NPL). On 5 August 1968 Dr Davies gave the first public presentation of work he had been doing on a method of moving data around computer networks called 'packet switching.'"

59 comments

  1. All times by Ian+Alexander · · Score: 4, Insightful

    It has often been said that change is the only constant in the 21st Century.

    I've never heard that applied specifically to the 21st century. It's an oddly-specific use of the phrase: does that imply that change has not been constant in other times? Empires grow and fall, cultures collapse or are swept away or conquered by the next Big Empire, customs change, ethnic identities change, etc etc. The only unique thing about the 21st century is that we've inherited a tradition of rapid technological change. Technology is important but it's hardly the only thing that changes over time and it strikes me as fairly myopic to single out the 21st century as a time of change.

    1. Re:All times by Jurily · · Score: 2, Insightful

      does that imply that change has not been constant in other times?

      Actually, it's an inherent property of the universe. You know, quantum physics and stuff.

    2. Re:All times by Anonymous Coward · · Score: 0

      Things starting to change at one point makes no sense. What caused things to start changing? A change?

    3. Re:All times by hey! · · Score: 1

      It's clearly not the case that the first derivative of the status quo is not a constant. Likewise I can think of things that are a constant that are not change (e.g. the number grams in a kilogram). Altogether I think that whoever it is who comes up with these expressions is not mathematically or scientifically literate.

      I mean, take a saying like "the more things change, the more things stay the same." What are we supposed to make of that?

      --
      Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
    4. Re:All times by Anonymous Coward · · Score: 0

      It's clearly not the case that the first derivative of the status quo is not a constant. Likewise I can think of things that are a constant that are not change (e.g. the number grams in a kilogram). Altogether I think that whoever it is who comes up with these expressions is not mathematically or scientifically literate.

      I mean, take a saying like "the more things change, the more things stay the same." What are we supposed to make of that?

      It means that while things continue to change they also do so in a cyclical way so that historical patterns repeat themselves.

    5. Re:All times by Ian+Alexander · · Score: 4, Insightful

      Altogether I think that whoever it is who comes up with these expressions is not mathematically or scientifically literate.

      Altogether I think that people who read phrases like "the only constant is change" and flourish a physical constant as counterevidence have completely missed the point of the expression.

    6. Re:All times by Eudial · · Score: 1

      Einsteinian relativity gets the blame for time.

      Quantum physics has enough to worry about as it is.

      --
      GAAH! MY PRINTER IS ON FIRE!!! PUT IT OUT! PUT IT OUT!
    7. Re:All times by Evil+Shabazz · · Score: 1

      What you point out is one of the many side effects of our modern "blog-news" internet world. The submitter is probably not schooled in journalism or maybe even any sort of story-writing. They were attempting to both introduce the idea of change as opposed to the subject of the story through use of the cliche and also introduce the 21st century as context of the story. Instead, they mangled the attempt and produced a bad sentence.

      I have to say, though - when I come to slashdot, I'm not really looking for quality journalism. The story is just the starting point for the conversation here.

      --
      Down with the career politician! SUPPORT TERM LIMITS
    8. Re:All times by Amazing+Quantum+Man · · Score: 1

      With apologies to Douglas Adams...

      Time is an illusion. Lunchtime doubly so.

      --
      Fascism starts when the efficiency of the government becomes more important than the rights of the people.
    9. Re:All times by CZakalwe · · Score: 1

      does that imply that change has not been constant in other times?

      No because he said it's the only constant of this century, that implies nothing about any other time, only that in the 21st Century, any other constants that might have existed in the past, no longer apply.

    10. Re:All times by Anonymous Coward · · Score: 0

      Or their first language isn't English. Northern to north-eastern Europeans in particular tend to be overly literal. Oddly, south-eastern Europeans are the opposite (Hungary, Bulgaria, etc).

    11. Re:All times by CZakalwe · · Score: 2, Insightful

      I mean, take a saying like "the more things change, the more things stay the same." What are we supposed to make of that?

      Well I always thought it meant that although many things will seem to change a great deal on the surface, when you look at a deeper, more fundamental level, the same old principles are still at work. Take the machinations of Politics as an example!

    12. Re:All times by settantta · · Score: 1

      The idea dates back way beyond then... the Ancient Chinese philosopher Lao Tzu (or Lao Tse f you prefer) wrote that "..the only thing which does not change is change itself." (very roughly paraphrased).

    13. Re:All times by ciderVisor · · Score: 1

      You got nothing to fear except fear itself.

      --
      Squirrel!
    14. Re:All times by RockDoctor · · Score: 1

      It has often been said that change is the only constant in the 21st Century.

      I've never heard that applied specifically to the 21st century.

      There are probably a million and one ways that this has been expressed. The way that sticks in my mind puts the blame on Solomon : he's bored being the brainy guy in the throne room, so decides to give some of the Grand Vizers, Lord High Muckamucks and High Heidjuns some brain exercise. He asks them to go away and come up with a factual statement which will always be true. Snipping various wrong answers put in to increase the story's tension, they eventually cook up "this too shall pass".

      I've no idea how old the story is, but the style makes me think this one goes back to Victorian times at least. Literature buffs can probably put another century on it.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  2. Re:Thank goodness for packet switching by Anonymous Coward · · Score: 0

    You're really struggling with this whole first thing, aren't you.

  3. Celebrate? by cpicon92 · · Score: 1, Funny

    I bet that guy from Sony would love to go back in time and stop this from happening.

  4. Re:Thank goodness for packet switching by Anonymous Coward · · Score: 0

    The last word is remembered.

  5. The Dawn of The Net by drkfdr · · Score: 2, Funny

    made me realize the intarnet is not tubes at all

    1. Re:The Dawn of The Net by fucket · · Score: 3, Funny

      You put the packets in the tubes.

    2. Re:The Dawn of The Net by jo42 · · Score: 1

      Not tubes. Pipes! Why? Pipes are bigger than tubes.

    3. Re:The Dawn of The Net by Tablizer · · Score: 1

      Well, CSS does act that way ;-)

  6. Changing change by Atmchicago · · Score: 4, Interesting

    It's an oddly-specific use of the phrase: does that imply that change has not been constant in other times?

    Re-read it. It says that the only thing that doesn't change in the 21st century is that things change. Arguably, things always change, in which case the phrase is vapid. At the same time, the rate at which things change is accelerating. Compare life in Europe, circa 1000 with 1100. Then compare life in Europe 1900 and 2000 - the differences are much greater!

    --

    You can lead a horse to water, but you can't make it dissolve.

  7. to be picky but, by Anonymous Coward · · Score: 0

    National Physic[b]a[/b] Laboratory

  8. Multiple sources by Tablizer · · Score: 5, Informative

    Paul A. Baran and Leonard Kleinrock also get credit for packet switching. It appears that multiple inventors independently (or semi-independently) came up with the idea and helped make it usable.

    1. Re:Multiple sources by grumling · · Score: 4, Informative

      There was also the alohanet in Hawaii, which introduced the concept of a shared channel and CSMA/CD:

      http://en.wikipedia.org/wiki/ALOHAnet

      The article deals with one aspect of packet switching, and it seems more like they were thinking about SONET-like systems.

      --
      "Well, good luck finding a judge that doesn't run a bestiality site."
    2. Re:Multiple sources by grumling · · Score: 1

      Ops! Take the /CD off the end.

      --
      "Well, good luck finding a judge that doesn't run a bestiality site."
    3. Re:Multiple sources by Anonymous Coward · · Score: 1, Informative

      Baran was first:

      http://www.livinginternet.com/i/iw_packet_inv.htm

    4. Re:Multiple sources by Zarhan · · Score: 1

      Actually, take out the CS at the start... :)

    5. Re:Multiple sources by elrous0 · · Score: 1

      Europeans have a thing about not giving an American credit for actually inventing anything. It's almost an obsession with them.

      --
      SJW: Someone who has run out of real oppression, and has to fake it.
    6. Re:Multiple sources by Tablizer · · Score: 1

      Europeans have a thing about not giving an American credit for actually inventing anything. It's almost an obsession with them.

      It reminds me how almost every country claims to have invented the airplane. The thing is that there were indeed many tinkerers with interesting contraptions, including in South America, not just Europe. The US lays claim to the invention by using the term "controlled flight". In other words, the Wrights' plane crashed less, and thus allegedly gets credit. But, the first to actually get into the air using an engine and wings is still a heated topic. It's a lot easier to get up than it is to come down nicely. Still, the first up should get some credit even if he/she "lands" keaster-up.
         

  9. Sounds Like Another How I Won the War Story by jmcharry · · Score: 3, Interesting

    A lot of people made contributions around that time. As a then undergraduate flunky in a physics lab, I remember playing with an early network that linked the Illiac II with a bunch of other computers. Since we weren't supposed to be playing with it, all we could do was come up with the login prompts, but several Midwestern universities were linked already. ARPANET sputtered to life in 1969, too soon for the touted theoretical contributions to be seminal. I don't doubt Davies did important work, but the article is over hyped.

  10. Leonard Kleinrock did it before that (1961) by cmarcond · · Score: 3, Informative

    Well ... it seems, Donald Davies was a little bit late on his work. According to Prof. Leonard Kleinrock (http://www.lk.cs.ucla.edu/), he had actually filed his Phd Thesis at MIT in 1961 creating the underpinnings for packet switching. (Kleinrock, L., "Information Flow in Large Communication Nets", Ph.D. Thesis Proposal, Massachusetts Institute of Technology, July 1961). About 7 years before Davies' talk. Although, they could have worked simultaneously on the same thing, it took years at that time to get something published distributed widely. Nowadays, we have slashdot!

  11. Packet switching at NPL by Anonymous Coward · · Score: 2, Interesting

    My Dad worked with Donald Davies. That's him on the far right in the pic on the BBC. He would have been 85 tomorrow.

    1. Re:Packet switching at NPL by Anonymous Coward · · Score: 1, Funny

      Why is this article about packet switching? It should be titled "Rare photo of Anonymous Coward's father found". And tell us how crack physiognomists are using the image to create a likeness of the elusive AC.

  12. Packet switching was originally developed... by stox · · Score: 4, Informative

    by Paul Baran in the early 1960's.

    http://en.wikipedia.org/wiki/Packet_switching

    Baran developed the concept of packet switching during his research at the RAND Corporation for the US Air Force into survivable communications networks, first presented to the Air Force in the summer of 1961 as briefing B-265 [1] then published as RAND Paper P-2626 in 1962 [1], and then including and expanding somewhat within a series of eleven papers titled On Distributed Communications in 1964 [2]. Baran's P-2626 paper described a general architecture for a large-scale, distributed, survivable communications network. The paper focuses on three key ideas: first, use of a decentralized network with multiple paths between any two points; and second, dividing complete user messages into what he called message blocks (later called packets); then third, delivery of these messages by store and forward switching.

    --
    "To those who are overly cautious, everything is impossible. "
    1. Re:Packet switching was originally developed... by Anonymous Coward · · Score: 1, Interesting

      And what about Louis Pouzin ?

      http://en.wikipedia.org/wiki/Louis_Pouzin

      Really I think it was an idea floating during the 60s that a lot of people have been exposed to.

    2. Re:Packet switching was originally developed... by Anonymous Coward · · Score: 1, Insightful

      The same is true for a lot of inventions. Seems to be that inventions just seem to have their time. The light bulb, the aeroplane, television, the telephone - there were a lot of people working on them at the same time, and if the recognised inventor had not managed it, someone else would have.

      A

    3. Re:Packet switching was originally developed... by Anonymous Coward · · Score: 0
      FFS read the article before posting.

      "There were other ideas around, like Paul Baran at Rand, but they were nowhere near as useful as what Donald Davies did in terms of size of packets and nodes," said Dr Pethica.

      "It was Donald who had the idea of making a set of nodes that you send packets of data to that find their own way through," said Dr Pethica.

  13. Where Wizards Stay Up Late by beatbox32 · · Score: 3, Interesting

    Interesting that this event just came up. I just finished reading Where Wizards Stay Up Late: The Origins of the Internet today. For those interested in the history of ARPA and internetworking development (and the people behind these developments - Davies, Kleinrock, Licklider, et. al.), I highly recommend this book.

    --
    "The purpose of learning is growth, and our minds, unlike our bodies, can continue growing as long as we live." - M.J. A
    1. Re:Where Wizards Stay Up Late by spauldo · · Score: 1

      Seconded.

      That's a great book, written by a fellow who worked with ARPANET development from the beginning. He starts out the book talking about attending a conference where his goal was to debunk the myth that the ARPANET was created for communication in the wake of a nuclear attack - he says that yes, packet switching was originally proposed for that purpose, but the ARPANET was a separate project and wasn't designed for that sort of fault tolerance.

      If you're ever curious about how things worked at BBN, why the IMPs were created to survive bomb blasts, or why a lot of the decisions in the early history of the internet were made, this is the book for you.

      --
      Those who can't do, teach. Those who can't teach either, do tech support.
    2. Re:Where Wizards Stay Up Late by Carik · · Score: 1

      Agreed -- it's a great book. My father worked with the ARPANET team, so I got to meet most of the BBN folks mentioned in the book over the years (most at dinner parties at one or another of their houses). Once I'd read the book, I went back and asked a bunch of them how accurate it was: they all had some nitpicking to do ("Well, it was a long time ago, but this piece isn't quite how I remember it...."), but agreed that it was the most accurate account they'd seen.

      Kate and Matt did a great job; it should really be required reading for anyone who's going to work in IT.

  14. change is now slower by Anonymous Coward · · Score: 2, Insightful

    Compare life in Europe, circa 1000 with 1100. Then compare life in Europe 1900 and 2000 - the differences are much greater!

    But has it really changed that much in the last 30-40 years?

    The majority of the largest changes in the last hundred years would be: electrification ('10s), radio ('20s), telephone ('30s).

    Secondary changes would be automobile growth ('40s), the mainstreaming of the automobile ('50s) and television ('50s). The most recent change since the 1950s would the mainstreaming of computers in the late '90s.

    I think the delta from before World War I and to just after World War II would be the greatest amount of change (just look at the technology used in each of those). The Roaring Twenties would be the greatest change. IMHO it's been mostly incremental technologically, but perhaps a bit more revolutionary from a societal point of view, as technology has been absorbed into our psyche.

    Even with something like the mobile phone, the basic idea hasn't changed since the early '80s, even though they've become more sophisticated. It's the social effects that have become more prevalent in the last five years. But someone who's used a touchtone (DMTF) phone in the '60s would be perfectly at home with a mobile (if they just wanted to dial, and not have to deal with most of the suck-ass address book UIs).

    1. Re:change is now slower by Anonymous Coward · · Score: 0

      Compare life in Europe, circa 1000 with 1100. Then compare life in Europe 1900 and 2000 - the differences are much greater!

      But has it really changed that much in the last 30-40 years?

      The majority of the largest changes in the last hundred years would be: electrification ('10s), radio ('20s), telephone ('30s).

      Secondary changes would be automobile growth ('40s), the mainstreaming of the automobile ('50s) and television ('50s). The most recent change since the 1950s would the mainstreaming of computers in the late '90s.

      I think the delta from before World War I and to just after World War II would be the greatest amount of change (just look at the technology used in each of those). The Roaring Twenties would be the greatest change. IMHO it's been mostly incremental technologically, but perhaps a bit more revolutionary from a societal point of view, as technology has been absorbed into our psyche.

      Even with something like the mobile phone, the basic idea hasn't changed since the early '80s, even though they've become more sophisticated. It's the social effects that have become more prevalent in the last five years. But someone who's used a touchtone (DMTF) phone in the '60s would be perfectly at home with a mobile (if they just wanted to dial, and not have to deal with most of the suck-ass address book UIs).

      You're right no big changes in the last 30-40 years. The internet has definitely not changed the world in in any significant way.

    2. Re:change is now slower by Tablizer · · Score: 1

      I think the delta from before World War I and to just after World War II would be the greatest amount of change ... The Roaring Twenties would be the greatest change.

      As far as impact on society, I'd tend to agree. The automobile, telephone, radio, and indoor plumbing made the biggest change of life-style. Interesting technologies have come since, but none of them have changed the way average people lived in such a dramatic way.

      (And, there's still no @#^%$ flying cars.)
           

  15. Telegraph and Mail by Comatose51 · · Score: 4, Interesting

    If you want to talk about easy digital, packet based networking, then the telegraph is worth a mention. Messages for electronic telegraphs were sent as packets that are later relayed to its final destination. It was also digital in the sense that each character was transmitted as discrete values. Another predecessor to TCP/IP based networking would be the mail system. While it wasn't digital, it was also packet based and as anyone who've used the postal system knows, it's only best effort. For added cost, you can get ack-like behavior with return receipt.

    --
    EvilCON - Made Famous by /.
    1. Re:Telegraph and Mail by Anonymous Coward · · Score: 0

      They were also digital in sense that people manipulated these ancient technologies with their digits!

    2. Re:Telegraph and Mail by dtmos · · Score: 1

      Exactly right. In fact, the relationship is even closer than the parent states. Telegrams have a true packet structure, with a header and payload. Further, the headers have distinct fields, including a unique message ID, message types, source and destination addresses, detailed QoS (Quality of Service) provisions, timestamps, and message length, just to name a few.

      The Western Union network used location-based routing, with smaller, local-area lines connected to hubs having dedicated point-to-point links to other hubs. When a link went down, control messages were sent announcing the problem to other hubs, and paid messages were re-routed.

      The ARRL National Traffic System, an amateur radiotelegraph network established in 1949, has many, many features "rediscovered" in modern wireless data networks, including:

      -A hierarchical network structure (a "network of networks")
      -A master-slave structure in each network, with a beaconing master (the "net control station", or NCS)
      -RTS/CTS channel access
      -Multicast messaging ("book" messages)

      Some of its other features, including the separation of control and data functions into separate logical channels (data is exchanged between hierarchical levels by designated representatives, not by the NCS, which controls each network), could still find application in wireless data networks today.

    3. Re:Telegraph and Mail by ThanatosMinor · · Score: 0

      Telegraph is arguably digital communication, but not at all packet-based. No more so than speech, anyway. If you choose to call a message a single packet, you're ignoring the underlying method of communication, where a link is established and then characters are encoded, sent, and decoded at the other end as just a long string. What's the packet here? What's the payload and what's the header?

  16. Ethernet by Anonymous Coward · · Score: 0

    The robustness of the technology is amazing. Part of my network uses 10Base2 to connect a fairly remote location to the rest of the more "modern" fast Ethernet.

    The Ethernet repeaters are some 20 years old, with discreet ICs, and thru-hole circuits. Only the power supplies have needed repair.

    Still, this is enough for 2-3 channels of standard-definition TV, (Myth TV) SIP and Skype VoIP, and miscellaneous other applications.

    Granted, a couple of machines now use as much bandwidth as was previously intended for an entire office, but the underlying tech is limited only by the processing power of the things connected to it!

  17. You and the CEO of Sony Pictures? by Mathinker · · Score: 1

    > But has it really changed that much in the last 30-40 years?

    Geez, you're so enmeshed in the Internet you don't even think about its existence!

    Or maybe you just live in the present. If you had a really good memory, you'd understand that just 10 years ago encyclopedias were (only) books and Wikipedia didn't exist. Actually, about 20 years ago the Internet as we know it currently didn't exist (yeah, geeks used it for email, listserves, FTP, maybe gopher).

    In the last 20 years, easy lossless copyability of audio/video/text content, and easy global dissemination have had far-reaching consequences for the content industries (or so they're ceaselessly claiming). Something those industries don't talk about, but is starting to be significant, is that people are more and more exposed to not-for-profit content generated by low-budget independent artists, we might even call them their peers (e.g., YouTube).

    > But someone who's used a touchtone (DMTF) phone in the '60s would be perfectly
    > at home with a mobile (if they just wanted to dial, and not have to deal with most
    > of the suck-ass address book UIs).

    You even get this wrong. The first thing he's going to ask is "How do I get a dial tone?".

  18. Autodin by Sqreater · · Score: 2, Interesting

    I was a Telecommunications Specialist in the military Autodin System (Automatic Digital Network) in the DCS from 1975 until 1979. I was a network troubleshooter - fault isolation and correction. This was a worldwide packet switching system for military communications and supported the NSA need to funnel intercept data back to the US from Menwith Hill and other bases. I could be wrong, but something seems wrong with the given timeline as there was a full-blown worldwide system in 1975 when I entered the service. I had approximately 150 circuits to bases that I was responsible for keeping up - modems, crypto gear, tropospheric scatter and microwave links carried our data (had HF radio too). Was there enough time to set that up? Was there a parallel development that is not showing up in technical history? Just a thought. We used a Philco-Ford, then Aeroneutronics Ford computer for routing. We had two Procs that swapped on error, and drum memory. I viewed the circuits by dialing them up on an "MTC" Monitor and Test Console, to watch the bit traffice on a dual trace oscilliscope. Things have changed so dramatically that I can go onto Google Earth to view my old base and note the changes that have taken place in the interim. I thought the advent of advanced technology would have caused my small base to shut, but that's not the case. It has been security hardened and 4 new large satellite dishes added.

    --
    E Proelio Veritas.
    1. Re:Autodin by idontgno · · Score: 2, Interesting

      Not to nit-pick, but AUTODIN was message-switched. (I worked AUTODIN software in the early '80s.)

      The distinction between message-switching and packet-switching is small but crucial. The quantum of messaging in a message-switched network is an entire message. That's why AUTODIN implemented overrides and interrupts, permitting a high-precedence message to override a long lower-precedence message. When that happened, the receiving switch discarded the partly-received lower-precedence message, received and processed the higher-precedence message in its entirety, and then began from octet 0 with the next message on the circuit addressed to it (which may be the message it partially received earlier--but with no persistence, it started from the beginning.)

      A packet-switched equivalent would hold the incomplete partial message in core (or disk, I suppose) and receive the packets of the higher-precedence message, assemble that message and process that message, and then continue processing the delayed (not interrupted) remainder of the lower-precedence message.

      Packet switching was, in its time, radical. It allowed organic solutions to problems like precedence-based circuit management in less wasteful ways than message switching. It was also sufficiently different from message-switching in behavior that the software for packet-switching had to be written pretty much from scratch, or bought from a vendor if you were lucky.

      That's the voice of experience speaking: our team wrote a very primitive TCP/IP stack for our Unisys 1100 mainframe, and never shook all the bugs out of it (mostly timing bugs, since realtime interrupt handling on the comm circuits were always a nightmare of race conditions.) We were never so glad when Unisys started offering off-the-shelf LAN hardware and TCP/IP software for those machines, and we could stop wrestling with our own ugly Frankenstein monster.

      --
      Welcome to the Panopticon. Used to be a prison, now it's your home.