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Leonard Kleinrock On The Origins of Packet Switching
An Anonymous Coward writes: "From Ben Sullivan's Tech Blog (http://www.techblog.com). An email from Leonard Kleinrock on why he really was the brains behind packet switching. It's a first-hand account from Kleinrock in a blog. A neat little journalistic scoop for bloggers, and some insights for techheads on Internet history."
"I invented packet switching"
-Al Gore
A previous discussion here.
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Oregon
That would have been interesting. Britain as the home of the Internet.
The possibilities of an alternate history are fascinating.
In any case some of it is a matter of research being done in parallel, which means that these sort of debates will take place as a matter of course.
"It is a greater offense to steal men's labor, than their clothes"
Umm, yes, it is that clever. When you send someone a letter (one of those cool paper things with ink on 'em), you expect it to arrive on time and in one piece. This is exactly what snailmail does. The postal service picks up your letter, routes it through their distribution channels, and delivers it to the recipient's mailbox. Now what if your company wishes to send out an enormous box containing for example a new big screen TV to some customer? You probably won't use regular mail, but have a heavier-duty delivery service handle it at a higher price because the postman would break his back lugging your box across the city. But what if there were no alternative? Man, that postman would be SLOW! Same goes for electronic bandwidth. If you'd send a single small e-mail out as a single entity (packet if you will), the chances of it arriving properly at the recipient's inbox are pretty good. This is because the tiny little email doesn't pull a lot of bandwidth and will relatively easily slip through more or less congested lines. Sending out the 2-hour video of your wedding as a single packet across a routed network is bound to give problems. Somewhere along the line the network gets congested because your huge video can't go throught he same pipe together with the next guy's MP3 collection. Result: digital roadblock and there is no such thing as UPS on the internet to deliver big packets. The smart bit on packet switching in analogy to snail mail (considering the fact that we're talking 1962 here) is this: you'd never chop that big screen TV into little pieces so a small army of postmen could swiftly deliver it to your customer and reassemble it on the spot. It must have required a pretty brilliant leap of thought to actually do this for data. Intuitively you'd think the risk of data corruption would be too great with this disassembly- reassembly-step. Luckily we're dealing with computers here, not humans, so packet switching actually did turn out a big success. PS. I know my analogy here is flawed, but hey, you get the point, right? ;-)
Learn from the mistakes of others. There isn't enough time to make them all yourself.
That is what Metcafe says.
Whichever idiot moderated it up deserves eternal ridicule.
Do IP packets only contain a single byte payload?
I've known a number of people to send two postcards because what they want to write doesn't fit on one; and they helpfully write "continued on next postcard", exactly the way that IP fragments do. And, somewhat rarer but an even closer analogue, when there has been a weight limit on lettermail, people have sent (for example) the first five pages of a long letter in one envelope, and the last three pages in a second envelope.
And then there's all the furniture which is shipped in parts for the recipient to assemble...
Tarsnap: Online backups for the truly paranoid
This is an excellent point. Packet switching really is an obvious idea, it is just the postal system done electronically. Watching these computer scientists squabble over these crumbs of creativity is embarrasing.
He has his very own webpage with information about the early days of the internet as well as his accomplishments.
IIRC, Ethernet was based on the "aloha" radio network in Hawaii, but there was packet switching long before there was Ethernet.
Whoever owns the patent, wins. Even that guy who said "Let's Roll"'s family lost their right to the phrase b/c someone quickly patented it.
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Let me give you the lowdown
From avi freedman's homepage: the Freedman doc - info on multihoming and BGP.
BR~z
sig?
Donald Davies is largely acknowledged for developing Packet Switching (and even coining that very phrase) at the National Physical Laboratory in the UK, however he was not American so he's largely ignored.
Packet switching refers to protocols in which messages are divided into packets before they are sent. Each packet is then transmitted individually and can even follow different routes to its destination. Once all the packets forming a message arrive at the destination, they are recompiled into the original message.
Most modern Wide Area Network (WAN) protocols, including TCP/IP, X.25, and Frame Relay, are based on packet-switching technologies. In contrast, normal telephone service is based on a circuit-switching technology, in which a dedicated line is allocated for transmission between two parties. Circuit-switching is ideal when data must be transmitted quickly and must arrive in the same order in which it's sent. This is the case with most real-time data, such as live audio and video. Packet switching is more efficient and robust for data that can withstand some delays in transmission, such as e-mail messages and Web pages.
A new technology, ATM, attempts to combine the best of both worlds -- the guaranteed delivery of circuit-switched networks and the robustness and efficiency of packet-switching networks.
...courtesy of Webopedia
The big breakthrough needed for the ARPANET was the militarized DDP-516 minicomputer, which was the first computer you could just ship someplace and expect it to work when turned on.
Kleinrock is claiming too much credit.
Yes, his work on queueing theory is important, at least to people concerned with math and network analytics. And if anybody gives a damn about analyzing the performance of a packet-switched network mathematically, then it'll fall back onto Kleinrock's work.
But what passes for packet switching nowadays -- "The Internet" -- is most certainly not the result of careful analysis! It works by brute force. It's inefficient. It is badly monitored and mostly unmetered. So Kleinrock's analysis, which might be useful, is ignored.
Anybody with half a sense of the math wouldn't dare try to cram constant-rate streaming traffic, like telephony or broadcasting, onto the IP Internet. It's inefficient as hell. Economy of scale is what makes it seem to work, compared to economy of specialization (what ATM would excel at). But that's the Internet's current ruling ethos -- if it seems to work, do it, even to excess.
The original inventors -- Davies, Baran, and the BBN crew -- were not doing mathematical optimization. They were hacking (in the good sense) something together and observing what worked. Kleinrock is like a guy who invents a great network management system that never gets turned on, but who still claims credit for the network that his system might have been able to manage.
And puh-LEEZ, don't give Vint any of the credit. He's made a great living as the Chauncy Gardiner of the Internet.
Multi-volume set, sent a volume at a time.
Multi-chapter book, sent a chapter at a time.
Newspaper serials, sent a column at a time.
I'm sure somebody has sent a longer missive, written on the back of postcards.
Seriously, it's typical for English to remove significant parts of words provided that the pronounciation doesn't change much. Also it's typical not to consider whether the new word is similar to already existing words. English speakers are very simple-minded in this regard.
If somebody, say, in Poland came to the market with a product called "Hot Dogs" (in Polish), they would go out of business immediately. And nobody would give a respectable site a name so closely reminding "bloated log".
absolutely. Even more so would be the way that containers are transported around the world by land and sea. Have you ever been to a modern container port? It's mind-bending.
That was classic intercourse!
(Be warned - this post is offtopic.)
;)
Your sig says "There is one thing humans can never do: be descendant from apes."
Computers descended from humans, and humans descended from apes. Therefore computers descended from apes.
"Destroy science and religion. Science would re-emerge exactly the same; but not religion." - Penn Jillette, paraphrased