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Vint Cerf on Internet Challenges
chamilto0516 writes "Phil Windley, a nationally recognized expert in using information technology, drove up to the Univ. of Utah recently hear this years Organick Lecture by Vint Cerf, one of the inventors of the Internet. In his notes, Vint talks about, 'Where is the Science in CS?' He also goes on to talk about real potential trouble spots with the Internet, but there is a bit on Interplanetary Internet (IPN). Apparently, the flow control mechanism of TCP doesn't work well when the latency goes to 40 minutes."
That is a easy problem to solve... Just set the TCP windows size VERY large.
Well... Duh!
I just assumed everyone ~knew~ we'd be using UDP between planets...
Sheesh... do I have to send a memo about ~everything???
Agile Artisans
Since when did the internet have 'inventors'? In its present form, it has evolved from many different projects and events, and no one person(s) planned for it to be what it is today. It's kind of like the technological equivalent of pizza, it became what it is today thanks to many different people who had different ideas in mind.
What an incredibly poorly written article. There was good content but it was like jogging through a field of boulders......
http://www.busyweather.com/
TCP assumes anything over 2 minutes is a lost packet.
Care about electronic freedom? Consider donating to the EFF!
Join moola.com, play games to earn money.
It's a person? I thought it was a number at first.
Apparently, the flow control mechanism of TCP doesn't work well when the latency goes to 40 minutes.
That's what subspace communication is for. I would hope that a geek of his caliber has at least watched some Star Trek.
" What an incredibly poorly written article. There was good content but it was like jogging through a field of boulders......"
Must be a former Slashdot poster.
so we can disseminate info like this
How long until P2P is Planet-to-Planet?
To quote a site that bothers to keep the quote around for Google's sake:And he did take initiative in creating the Internet. In fact, he pushed funding for it through a congress that was convinced that anything attached to the military (and keep in mind that NSF and DARPA *are* connected to the military) was "the enemy". I heard Gore speak back then, and he was passionate about the creation of a national research network and how important it was.
The Internet is here with us today as much because of the funding as because of the science, and Gore was the money man.
Persoanlly, I find some of his politics a bit extreme, but like or hate liberal politics, you have to admit that the media dropped the ball by not calling Bush on this.
"Since when did the internet have 'inventors'? "
The same way TV did.
Somehow I don't think he will be able to convince the Google boys that there is no science going on on the Internet.
Sigh.... again the Al Gore thing, and again it's modded as funny. It's not. It's a failure of our media to shoot down bad politics.
It was meant as a joke. In every story about the internet, someone invariably posts the Al Gore nonsense and someone else posts the "rumors on the internets" quote from GW. Maybe you missed the "let's get two out of the way" in the subject line.
I think everyone knows this. It's just funny to say. Well, was funny to say 5 years ago. Now it's jsut old.
Oh, riiiight. Gore didn't try to claim he was responsible for the Internet.
What bullshit.
Face it. Gore did try to take credit for "inventing" the Internet, in his usually wooden way.
Gore deserves what he gets, just like W deserves what he gets for saying crap like "misunderestimated".
There was a classic sci-fi short story from the 1940s or 1950s on this topic. The problem was "solved" by someone's mother who just happened to be in the "control room", baking cookies or some such. She basically proposed a full duplex scheme where two parties just stream data to each other, sending and listening at the same time, and you send a retransmit request if you miss something.
I heard Vint Cerf speak at an e-business conference (remember when those were popular?).
He talked extensively about how the layered architecture of the internet poses a serious challenge to business models. The fact that any application can communicate through any physical medium (of sufficient bandwidth) was great for interoperability, but hard on businesses that provide the physical layer.
The problem is that all of the value is in the application layer -- people want to run software, download movies, chat with friends, etc. Whether the data flows on copper, fiber, or RF is irrelevant to the end-user and the layered architecture ensures that this is irrelevant. In contrast, a lot of the cost is in that "irrelevant" physical layer -- the last mile is still very expensive (we can hope WiMax reduces this problem). This gulf between cost and value forces physical infrastructure providers into a position of being a commodity providers with severe cost competition. If the end-user doesn't care how their data is carried, then they tend to treat bandwidth as a commodity.
I think he was wearing his MCI hat at the time of this talk and was influenced by the beginnings of the dot-com crash. MCI's subsequent bankruptcy was not surprising. Understanding this issue explains why telecom companies don't want municipal wifi and insist that you only network your cellphone through their networks. The only way to make infrastructure pay is to bind the high-value software application layer to the high-cost hardware layer. But this strategy violates the entire layered model and enrages consumers.
Two wrongs don't make a right, but three lefts do.
Well, and maybe having his own website up there at phil.whendley.com.
Seems kind of far from a Nationally recognized expert to me. I'd never heard of him - why do I associate his name with a talk that Vint Cerf gave and apparently this guy gave no value too, other than driving there and listening
I have mod points and I am not afraid to use them
Even if CS came up with a scientific solution to improve code quality, it would be an interesting exercise to see if the industry will be willing to absorb the costs associated with such a solution. Especially in an environment where end customers are well-trained to accept and deal with software quality issues.
Then that is why we have a gateway, and we use that to bridge two internets. Or, invent some communication that is instant. :D
Student Research and Development
40 minutes = 2400 seconds
Speed of light = 299,792.458 kilometers per second
Distance from Earth to Mars: 55,700,000 kilometers (minimum) 401,300,000 km (maximum)
Time of travel at speed of light to mars: 401,300,000/299,792.458 = ~1339 second
Since Mars is supposedly the first place we're likely to go farther away than the moon it seems that we are fine for now.
Right? Or is there not a way to send data in form of light, or do radio waves travel slower than light?
Anyway, someone correct me here
"Oh, you hate your job? There's a support group for that, it's called everyone, they meet at the bar."
Over a 100Mb LAN the difference is effectively nothing, but once you involve slow and lossy networks the difference is considerable. The impact is great enough over terrestrial radio nets and is a zillion times worse interplanetary.
Let's say you have a rover that sends a position message once a second. What you're really interested in, typically, is the most up to date info. If you're using tcp, then you won't get the up to date info until the retries etc have been done to get the old info through (iie. it's noon, but the noon data is not being sent because we're still doing the resneds to get the 8 am data through). This means that the up to date info gets delayed. With udp the lost data is just ignored and the up to date data arrives when it should.
Of course ftp still (might) be a useful way to shift large files etc, but often the udp equivalents (eg. tftp instead of ftp) will be more apropriate.
Engineering is the art of compromise.
The UN isn't doing that much better, and the ITU is only for their own power.
h istory/
BTW, Vint Cerf didn't invent the internet, he co-invented TCP/IP.
The Internet is a much older vision.
You can read some of it here: http://www.computerhistory.org/exhibits/internet_
Since latency's going to be over lightyears away
Umm... huh? Latency is a time period. Lightyears are distance units. It's like saying "my car is a metre faster than yours".
"Radio waves are a kind of electromagnetic radiation, and thus they move at the speed of light."
Just found that on a web site so it must be true
"Oh, you hate your job? There's a support group for that, it's called everyone, they meet at the bar."
slashdot software fuckedup the url again, remove the space in there...
I thought, years ago when I was looking at it, that IPv6 had a TTL that was modifiable, and thus wouldn't time out.
....
But, as a practical matter, it would work better as an FTP request does, where you stream the data in blocks and resend any missed blocks later. This would work fairly well for lossy protocols like JPEG or suchlike, but a good image format should be able to handle it, but time stop/start protocols might get glitched and would have to be replaced.
Anyone for MP7? TUFF instead of TIFF?
The other question is, would this be on the same network, or would, given the very small number of network nodes concerned, it be on a network that we bridge to and translate as needed, buffering the data streams on each end.
Now, if you had a martian sandstorm for a few days, that's probably not going to be that helpful, but you get the idea
-- Tigger warning: This post may contain tiggers! --
Of course, that's got me thinking about Pandora's Star again and now I'm depressed as it has been 12 freakin' months and Peter F. Hamilton still hasn't completed Judas Unleashed.
But seriously, imagine if CERN discovered a workable way to make microscopic wormholes. All you'd need is one big enough to send a stream of photons through. Hook up your optic fibre and you've got yourself a zero latentcy round-the-world communications network. It'd certainly change gaming.
How we know is more important than what we know.
Double the distance.
And the 40 minutes was pulled out of a rectal database - it doesn't mean anything. TCP/IP timeouts are usually on the order of a minute or two, IIRC. (been a long time since I've been down in that code...)
It's like saying "my car is a metre faster than yours".
Yeah? well mine can do the Kessel run in 12 parsecs!
FGD 135
shame he works for the #1 spam support company in the world.
his company adds new spammers on an almost daily basis, just check the dates on the various sbl records.
Lawyers, MBA's, RIAA? A jedi fears not these things!
fuck I said this post wasn't a troll, I should get like +infinity insightful.
That sounds like a hardware problem to me. Therefore, most computer scientists will ignore it.
Have you read my blog lately?
The Internet is a much older vision.h istory/
You can read some of it here: http://www.computerhistory.org/exhibits/internet_
I know, I was on the first ARPANET. Back when I was at SFU, and 1200 baud was something you couldn't even get at the UBC labs.
So, yes, technically, Vint Cerf didn't invent the Internet per se, but then TCP/IP is what most people think of as the internet. And Al Gore was the primary lead on getting funding, so he did invent the Internet, since that was ARPANET, the real internet.
And, yes, I was in the military back then. But it's none of your business.
-- Tigger warning: This post may contain tiggers! --
Wow. If I had known that he was such a celebrity, I probably would have paid more attention in his Enterprise Systems class at BYU.
I guess it's nice to learn from someone important who doesn't act like the world revolves around him.
"With sufficient thrust, pigs fly just fine. However, this is not necessarily a good idea...."
RFC 1925
I found it! It's a 1962 story by Asimov!
Therefore, most computer scientists will ignore it.
Until it comes time to write drivers, then they'll all be whining about inconsequential things like "dammit, how the hell am I supposed to assert this pin AND move 3KB of data into the device, all within a single host clock cycle? Did the engineer smoke his timing diagrams?"
Latency is measured in units of time. Lightyears are a measure of distance.
TCP's no good using standard broadcast methods
Huh? If I knew what you meant to say, it'd be easier to show you were wrong...
We need something that'll be as fast as fiber, but will stretch way way longer in distance.
So, like, line-of-sight laser communication?
Current radio's a broadcast. Can't do that, especially with package leakage.
How do you think we're communicating with the Mars rovers now? Or other planetary explorers?
I belive there was some experiments in quantum transmissio of data, in which an electron was split and one half sent to Munich, the other sent to Venice, and transmissions where near-instantaneous.
You can instantaneously determine what the other side received, but no information can be transmitted this way.
I see you have a low user-id, and therefore have learned to get modded up for saying stuff that is nonsensical and wrong. I must admit I'm impressed. I earn all my mod points the hard way.
Since latency's going to be over lightyears away, and TCP's no good using standard broadcast methods...
Lightyear is not a metric for time time, it's a metric for distance. Light travels @ 186,000 miles per second, a light year is equivalent to 186,000 * (60sec*60min*24hrs*365.25days) or approximately 5,869,713,600,000 miles.
Right now we have copper, fiber, and radio. We need something that'll be as fast as fiber, but will stretch way way longer in distance.
As far as I know fiber (optics) use light to travel within the cable. This means that the fiber cable is limited to the speed of light. Radio broadcasts, much like visible light, are forms of energy (electromagnetic) that travel at the speed of (get ready for this) light.
If you had a fiber cable from here to Mars, the latency would be the same as radio. It would most certainly have better throughput, but that's another story.
Can I get an eye poke?
Dog House Forum
I think people generally don't understand what computer science is. CS isn't a 4 year degree to learn how to program or set up a network. It's about having the theoretical background to be able to analyze and evaluate comptuter technologies. Classes like automata theory and theoretical data structure classes are necessary to be able to both 1) apply a real solution to a problem and 2) be able to argue the validity of that solution. There is a lot of science in CS.
Vint hates the chaos of evolving systems and identifies all the protocols in flux. Most solutions not offered. Vince will be able to call home from Mars. I skimmed it, sorry.
So Gore deserves to be essentially forgotten, rejected by his home state.
And Bush deserves 8 years as President, a high probability of solidly tilting the Supreme Court for the rest of MY life, legislation letting his VP's company off the hook for asbestos liability knowingly purchased years before, etc, etc, etc. Maybe I should throw my dictionaries away, too.
I'm with Captain Janeway in her dislike of temporal mechanics, but this seems like a problem the crew in TOS solved by slinging the Enterprise one way or another around the Sun. Sling the data packets x number of times around the Sun and fling them the appropriate distance into the future, or, possibly, on occasion, into the past. But then again I could be wrong; as noted above I hate temporal mechanics.
"Academicians are more likely to share each other's toothbrush than each other's nomenclature."
Cohen
I'm not surprised when I see completely non-sensical posts get modded up on Slashdot anymore, but this has to be the most blatant example I've ever seen.
That this post got to +5 Interesting is proof that Slashdot's community moderation concept is a failure.
>> That sounds like a hardware problem to me.
heheh. that sounds like an application developer to me...
http://request-header.info
You can't transfer information over entangled particles. Furthermore, faster than light information transfer violates relativity.
Since most computer scientists are mathematicians at heart, they'll solve the problem by saying: ``Assume a network of super-luminal communications devices.''
See what I've been reading.
Since latency's going to be over lightyears away
Latency is measured in units of time. Lightyears are a measure of distance.
He could be referring to the latency incurred with a transmission distance of a light year... What is the latency of a lightyear? Assuming light speed communication, one year. Of course, add a bit for frame/packet decode...
Yeah, the rest of the post is meaningless... Kinda like all of this one!
I tihnk the problem lies with the poster (this means you) not knowing how to make a proper link.
Realtime communication with a Martian node is physically impossible. It's simply too far away.
Realistically, we might see a proxy architecture as follows:
1) All traffic is "queued" at an earth-bound substation. Communication is TCP-reliable to this node; transport layer acknowledgements are degraded to "message received by retransmitter" (end-to-gateway) rather than "message received by Mars"(end-to-end). Since both Earth and Mars are in constant rotation, a "change gateway" message would need to exist to route interplanetary traffic to a different satellite node (think "global handoff").
2) Transmission rates from Earth to Mars are constant, no matter the amount of data to send. Extra link capacity is consumed by large-block forward error correction mechanisms. Conceivably, observed or predicted BER's could drive minimum FEC levels (i.e. the more traffic being dropped, due to the relative positions of the Earth and Mars, the less traffic you'd be willing to send in lieu of additional error correction data.
3) Applications would need to be rewritten towards a queue mentality, i.e. the interplanetary link is conceivably the ultimate "long fat pipe". Aggressively publishing content across the interplanetary gap would become much more popular. As much content has gone dynamic, one imagines it becoming possible to publish small virtual machines that emulate basic server side behavior within the various proxies.
You'd think all this was useless research, as there's no reason to go to Mars -- but TCP doesn't just fail when asked to go to Mars; it's actually remarkably poor at handling the multi-second lag inherent in Geosat bounces. Alot of the stuff above is just an extension of what we've been forced to do to deal with such contingencies.
--Dan
Absolutely not. Gore entered Congress in 1977, well after any point that could reasonably be construed as the "creation" of the ARPAnet/Internet. It's true that he never claimed to have "invented the Internet" but what he did say is still completely untrue.
What I'm listening to now on Pandora...
Gosh, I can't believe there hasn't been a stargate joke yet. Amazing.
So Vint hates the most important property of the Internet, emergence.
...
Interesting
I know. It makes me stop reading slashdot every couple days, because I get so fed up with the misinformation.
In the 70s, NASA had little tiny satellites sending back images (hint to the others: that data was reliably transmitted too!) of planets from places much much farther away than Mars.
People don't realize, but even there are problems using TCP to talk to satellites in orbit around Earth. What happens is as the satellites move, your RTT slowly grows (as it gets further away), and it gets to a point where it comes time to switch to a new satellite. So your RTT will instantly jump.
TCP was not designed with this mind (Actually, TCP was not designed with many, many current situations in mind, and has had many hacks tacked onto it). But people are trying to work out ways to minimize the effect.
"Strogatz is a Cornell mathematician and pioneer of the science of synchrony, which brings mathematics, physics and biology to bear on the mystery of how spontaneous order occurs at every level of the cosmos, from the nucleus on up. In this eminently accessible and entertaining book, Strogatz explores the mysterious synchrony achieved by fireflies that flash in unison by the thousands, and the question of what makes our own body clocks synchronize with night and day and even with one another."
Sync
$ ping beagle2.mars.sol # --- .sol TLD for our solar system
PING beagle2.mars.sol (10.42.0.2) 56(84) bytes of data.
64 bytes from 10.42.0.2: icmp_seq=1 ttl=64 time=2485995.132 ms # --- about 40 min
64 bytes from 10.42.0.2: icmp_seq=2 ttl=64 time=2485995.197 ms
64 bytes from 10.42.0.2: icmp_seq=3 ttl=64 time=2485995.163 ms
Destination Host Unreachable # --- beagle2 crash
Destination Host Unreachable
Destination Host Unreachable
Sorry for this obligatory UNIX joke, but I couldn't resist !
For me, its not science if it doesn't involve the methods of empiricism. Observation, hypothesis, repeat.
The only time this really happens with computers is troubleshooting.
Programmers may think in a logical or analytical way, but thats not science. And its a good thing to. If programmers weren't allowed to make stuff up as they went along but instead had to use scientific method for everything they did not many progams would be completed.
actually no - the speed of light changes depending on the medium it is passed through. data travelling through space would approach the speed of light through a vacumm, the number you're using in your equation for a light year. however, the speed of light in fiber is about 30% slower due to the relatively higher refractive index in the cable and thus would be much slower than radio transmissions.
a ction_with_transparent_materials
more info can be found at: http://en.wikipedia.org/wiki/Speed_of_light#Inter
Ok, I admit I didn't RTFA, but this is just stupid. Why would anybody even thing about sending an interplanetary spacecraft out expecting to communicate with it using a determanistic protocol. Is this a joke, or what? The engineering that goes into designing anything that will be sent off-planet is incredible. Even satellites are designed with systems that not only deal with the few-second latency, but also account for the relativistic influences on time differences due to gravity.
Ok, maybe this is a joke, but it's poor attempt at one if it is. I mean, 40 minutes! It's only, what, 9 minutes at light-speed to the sun. Who TF is he talking about communicating with?!?!?
"Somebody has to do something. It's just incredibly pathetic it has to be us."
--- Jerry Garcia
That was the most incomprehensible blurb I have read on Slashdot.
> Apparently, the flow control mechanism of TCP
> doesn't work well when the latency goes to 40
> minutes.
UUCP, however, works just fine.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Al Gore?
Get your Unix fortune now!
Consider it more of 1/infinity insightful.
[some guy]...a nationally recognized expert in using information technology, drove up to the Univ. of Utah
Got denied plane tickets by DHS, eh?
More importantly, did he get to meet Brunvand while there?
We know almost nothing about making programming more efficient and systems more secure and scalable. He characterizes our progress in programming efficiency as a "joke" compared to hardware.
It's definitely a joke - and the real joke is that it can't even be characterized as "progress". The programming of today is worse than it was a couple decades ago and consistently declines. I have talented friends who have dropped out of the industry in disgust over what passes as programming nowadays.
Maybe Vint Cert should be talking about the evils of "computer science" being taught around Java, or the fact that many CS programs have become little more than glorified job training.
According to Cerf, "The first demonstration of the triple network Internet took place in July 1977". He refers to this event as the "Birth of the Internet". Prior to that, researchers could send messages but had to be very familiar with the underlying technology.
In a September 2000 email, Cerf and Kahn give Al Gore much credit in the development of the Internet: http://www.mintruth.com/wiki/index.php?Al%20Gore%
Two excerpts:
Look no further:
http://www.ccsds.org
(Vint Cerf has a irons in this fire)
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
Is a complete and utter joke.
It doesn't matter what Cerf says regarding Al Gore's advocacy/enthusiasm/promotion of the Internet once he was already in Congress. Al Gore's claim was he "took the initiative in creating the Internet", which simply can't be true because the Internet already existed before he took part in *any* initiative involving it.
Face it, Gore either didn't understand what he really did (and thought he DID help create the Internet), or he intentionally was misleading about his involvement. The latter could be to inflate his own sense of accomplishment or to deceive others as to the nature of his accomplishment. The fact he didn't own up to this quickly and completely is his own character flaw.
Bruce
The most obvious indication of the problem -- my personal pet peeve -- is that nobody can define bit anymore... Even Wikipedia currently omits a crucial part in its definition -- the two mutually exclusive states also need to be equally probable, otherwise data compressors stop working :-)
In Soviet Washington the swamp drains you.
Anyone heard of delay (or is it disruption?) tolerant networking? I could've sworn I saw an article on it on /. a while back ... http://www.dtnrg.org/ ... is Vint in on that too?
Hmmm, I'm rambling. Must be getting old.
No, it's proof that mods have no clue what they're moderating.
February 9th, 2009 8:55pm: Slashdot becomes self-aware.
The definition of a bit has nothing to do with probability. What a bit represents might not actually be digital, but the bit itself is.
It doesn't even make sense to say a 1 bit has an equal probability of being a 0 bit.
You spent to much time thinking about compression and qubits I think.
I've written thousands of lines of C code at work. Here is how I do it.
Keep it simple -- complex programs should only consist of hundreds if not thousands of easy to understand code blocks and functions.
Think like a CPU -- this skill is very helpful as it enables me to break complicated programming tasks down to almost the assembler level before coding it in C. Once you have and understand the 'big picture' all you have to do is type the details of the implementation in off the top of your head. Be sure to spend time with code expressions that evalueate to true or false. I mentally execute such code in my head then compare those results to an actual program run to verify my assumtions or correct my code.
Standardize your variable names (no, I don't use Hungarian notation) for non-important variables. For example, when mucking about with a file in C you need two or four things: variables to hold the input/output file names and the FILE variables themselves. I name mine infnam, outfnam, inf, and outf whenever and wherever I need them.
Reuse code bits and functions and re-name variables as needed as much as possible.
C'mon programmers, simple stuff like file copying shouldn't take a bunch of code to express. For example, my file copy function I wrote and use time and again has only 22 lines of code in it (not counting blank lines or lines with only braces). Deliberately making the software you write complicated is stupid and will not help you in the future should you or someone else have to modify it.
Always indent and 'bracify' your code before you add more nested code within -- DO NOT add the closing braces when you 'get around to it'. Not doing this will usually result in tons of compile-time errors due to missing or extraneous closing braces.
Hopefully, this post will help a fellow C programmer (or any other programmer for that manner).
Signed,
A programmer who wants to remain anonymous.
If I had points I would have modded you up, just like I modded this one up: http://slashdot.org/comments.pl?sid=146002&cid=122 31094
So far my mod has been rated 85% fair. What the fuck is wrong with you metamods?
Remember when Achimedes said 'Give me a place to stand and I can lift the Earth.'? This all involved a lever and fulcrum system big enough to multiply the downward force applied by Archimedes into a strong enough upward force able to 'lift' the Earth.
The same rationale is at work for FTL communications in this (ever so faintly) plausible scenario:
Imagine there was intelligent life on some planet in the Alpha Centari star system. This is about 4 light-years away. It would take light or some form of radio transmission FOUR YEARS to get there.
Now imagine you had 24 trillion mile long rod spanning the Earth to said planet. With this setup, one could send Morse Code to the other planet instantly by merely moving the rod back and forth with your hand.
This looks like true (though crude) FTL communications to me.
Of course, the above is all but likely impossible simply because the rod would have so much mass it'd likely collapse into a black hole the instant after it was created.
As a thought experiment, FTL travel/communications in this manner seems to be possible. In real life it is essentially impossible due to manufacturing problems and/or the laws physics concerned with gravitation.
That's strange. I thought that issue would have been worked out by RFC 1149 or CPIP. You would think that 40 minute transit times would be a quick ping when using the Carrier Pigeon Internet Protocol (CPIP).
Restore America: Dr. Ron Paul for President!
Good point. Layered networks in the end all result in one way of billing. A fixed fee for the connection and data, with maybe some differentiation in the amount of oversubscribtion. Say everybody would get a 100mbit line, 1:10 oversubscribed, but companies can also choose 1:2, 1:1 and 1Gbit or 10Gbit lines with appropriate pricing. The most cost effective way of building networks would then be one network operator and multiple service providers on that network. This might however lead to a lack of incentive for the network operator to improve the network. For more info:
s tupid.html
Http://www.worldofends.com
http:/www.isen.com/
Use Adsense for Charity
Pushing the rod would merely cause a shockwave in it, which would travel at the speed of sound in whatever material the rod was made of.
>With this setup, one could send Morse Code to the other planet instantly by merely moving the rod back and forth with your hand.
Bzzt, wrong, the motion gets transmitted at light-speed. Ask your local physicst (or just read one of the pop books on relativity) for details.
...which is already being researched by the NASA and the IETF: more info.
Pirate Party UK
So adding The Whole Universe would be euh 'tricky' ? /. article so we'll be fine with tcp/ip for now. /. allready has a chosen a relationship with a computer..
Still apparently there are only 3 cows on mars according to another
We can as, far as i'm concerned, also not bother.
I am pretty sure Alice wins in a blind intelligence test with a cow anyway.
Prob'bly even when you DO see her and the cows.
In fact i think every one on
Allthough i don't want to insult the slashdot population minority that lives with a cow..
Sorry, wouldn't work. There's no such thing as a perfectly rigid object. In a short rod, the effect isn't noticable, but in a an extremely long rod, the action of one end tanslates to a compression wave that travels down the length of the rod. It probably would end up moving at about the speed of sound through the rod, but nothing close to light speed, let alone faster.
e ling+transmission&btnG=Google+Search/
Of course, given the length to width ratio of such an interplanetary length rod, trying to nudge something at one end by pushing on the other would literally be like trying to push something with a piece of string, it'd just be too flexible.
On the other hand, there is a phenomenom known as quantum tunnel transmission that has allegedly been shown to transmit information at 4.7 times the speed of light over short distances:
http://www.google.com/search?hl=en&q=quantum+tunn
(click on link: Literature on Faster-than-light tunneling experiments, for some reason, it can't be linked directly?!?)
The U.S. really needs an English to Wisdom dictionary.
On the other hand, there is a phenomenom known as quantum tunnel transmission that has allegedly been shown to transmit information at 4.7 times the speed of light over short distances:
http://www.google.com/search?hl=en&q=
But, did you RTFA that you mentioned? Nowhere in nthe article you mention does it indicate that, at any point they were able to transmit ENERGY or INFORMATION at a speed exceeding light.
Read it again, and maybe you'll get it this time (?)
I have no problem with your religion until you decide it's reason to deprive others of the truth.
I've long understood that CS is in fact a branch of mathematics, and not a science at all.
Science is about empircal observations and experiments. That has one place and one place alone in computing - the science of reverse engineering. And that's called "engineering".
See, we're not good at naming things here.
"Absolutely not. Gore entered Congress in 1977, well after any point that could reasonably be construed as the "creation" of the ARPAnet/Internet."
The technology was there at that time, but it was in the early to mid 80s that it became widely available, and that required funding. You have to realize that at the time, you didn't just go to your telco and say, "Hi, I'd like a T3 for data, please." It was a special and very expensive thing to get a circut installed that could be used for such purposes.
The federal government was very divided on this point, and it was because of the funding that was pushed by Gore that the Internet happened when it did. Would it have happened anyway? Almost certainly, but I doubt that it would have happened as WELL. The U.S. military research community was the ideal place for the Internet to start, and had it required business to get it off the ground in those early days, we might be facing a very different beast today.
Al Gore invented the Internet!
Now where did I put my ansible?
"It doesn't matter what Cerf says regarding Al Gore's advocacy/enthusiasm/promotion"
Again, this misses the point. He didn't avocate it, he PAID FOR IT.
By way of analogy: When your kid is playing around in the garage and invents a new computer, so you give him a million dollars and get all of the zoning considerations worked out so that he can start selling them from your house, you have just as much a right to call yourself a founder of the computer company as he does.
The "IP network on which the Internet is built" was not Al Gore's baby, but the network we use and rely upon today is here because he "took the initiative in creating" it just as much so as the people who put technical expertise into it. He deserves full credit for that.
This is not politics, this is just assigning credit where it is due, and I was saying this long before I even knew what Gore's politics WERE (he was just some Congress-critter as far as I was concerned in the 80s).
>Again, this misses the point. He didn't avocate
>it, he PAID FOR IT.
Again, this misses the point. He didn't claim he paid for it; he claimed he took the initiative in CREATING it. Which he didn't. By the way, he didn't pay for it, either -- it already existed, and we, the taxpayers, footed the bill.
>By way of analogy: When your kid is playing
>around in the garage and invents a new computer,
>so you give him a million dollars and get all of
>the zoning considerations worked out so that he
>can start selling them from your house, you have
>just as much a right to call yourself a founder
>of the computer company as he does.
Your analogy is flawed. It's much more like the kid had already founded his company and was selling his computers, and then Al Gore was a VC who came along and invested a bunch of money to help expand it. Al Gore deserves credit for helping the company, but he in no way has a right to be called founder or, even worse, inventor of the new computer.
>The "IP network on which the Internet is built"
>was not Al Gore's baby, but the network we use
>and rely upon today is here because he "took the
>initiative in creating" it just as much so as
>the people who put technical expertise into it.
>He deserves full credit for that.
No, he doesn't. He deserves credit for supporting a pre-existing Internet, but in no way could he be credited with help creating it. He could have said EXPANDING the Internet, or maybe even MODERNIZING the Internet, but not CREATING the Internet.
>This is not politics, this is just assigning
>credit where it is due, and I was saying this >long before I even knew what Gore's politics
>WERE (he was just some Congress-critter as far
>as I was concerned in the 80s).
I don't care how long you were saying it; you were wrong to say it then and you're wrong to say it now.
Bruce
.. unles it's implementing mathematical algorithms. That is why formal proof tools against a specificaation have been fruitless. There is no way that a static specification can contain the total description for what all the users want out of a piece of software of any complexity. People's needs and understanding changes. Sometime they are even shaped by the software as it is being used. Given that, it is at the prototyping and debugging stage that much of the shape of a piece of SW solidify. So what is to be gain by using formal methods at all?
A parable:
John Scientist proposes a new way of getting to orbit - a Space Hook. He and his team build an experimental version, used among researchers for launching small, lightweight experiments. It is used in this way for a number of years, but most of society pays it no attention, as rockets are flashier and most people don't pay too much attention to what those space scientists are up to anyways.
After a few years, Jane Politician notices how useful and efficient the Space Hook is. She thinks that it would great if it would be used by many people and projects who are going into space. She convinces congress to fund The Fishhook, a larger and more capable Space Hook. Millions of dollars are spent, and the Fishhook is deployed, making it possible for researchers, companies, and governments to go into space cheaply. Of course, not a lot of people have a need to go into space, but it makes things much easier for those who do.
In fact, after the Fishhook has been used for a few years, it becomes the usual way of getting into space. Eventually, because it is so easy to get into space now, Herbert Hooker starts a movement called Hooking, in which average everyday people go into space to start new lives. Hooking becomes a staple of popular culture, and the new frontier for society.
Years after the beginning of this parable, Jane Politician is running for Potentate of Mars. She says in an interview that she took the initiative in creating the Hook, hoping that the popularity of Hooking will help her cause. Her opponents point out that John Scientist really created the Hook, and she is arrogantly claiming credit not due to her. Even when John Scientist puts out a press release thanking Jane Politician for her help in funding and promoting the use of the Fishhook, many people felt that Jane Politician was lying about "taking the initiative in creating the Hook".
Did Jane Politician create the idea of the Space Hook? Obviously not. John Scientist did that.
Did Jane Politician take the initiative in creating the Fishhook? Yes, she did.
So did Jane Politician lie and take credit for something she did not do? You tell me.
That's also the standard sci-fi authors' response to this problem.
Have you read my blog lately?
Bruce is obviously either:
a) blindly partisan, or
b) blindly engineering-biased or
c) all of the above.
In any case he's obviously arguing not as an interested, engaged party but as an advocate for a particular position of which he is a True Believer. As such any response merely gives him another opportunity to get his leader's point across.
It's not such a dumb idea. Retransmission sucks when latency is high.
.
:).
So if you are going to use IP between planets it's not going to matter so much whether you use UDP or TCP, after all the link layer communications protocols will ensure the message delivery in 99.9999% of the cases (add more 9s depending on usage)
Basically what is likely to happen would be all data would be sent with signals that have tons of forward error correction. So that even if only 0.1% of the signal gets through successfully they can still reconstruct the message, so that there is no need to retransmit. If the message doesn't get through the first go, something exceptional is probably happening.
If there is a need to retransmit - the application (and people) might as well know anyway that there is a problem, and judge whether a retransmission is desirable - rather than waiting for an indeterminate time for TCP to retransmit and finally get the data.
After all maybe some antenna somewhere is broken or knocked the wrong direction. So the receiver (application/human) might as well be informed that something exceptional has happened and send a _different_ message of their own (rather than ask for a retransmission) and notify the sender.
The applications using the network are likely to be quite different anyway - not like anyone is going to click on a link and wait hours for a page to appear. You'd probably have stuff like HTTP/FTP by mail
Or Google/search by mail either send a batch of queries, or send an AI query agent program/script over to do queries (and make new queries based on the results).
Good point, forgot about that in my calculations. So I guess this means that fiber has about 30% higher latency than radio in the large vacuum that is space.
Can I get an eye poke?
Dog House Forum
(click on link: Literature on Faster-than-light tunneling experiments, for some reason, it can't be linked directly?!?)
What do you mean, can't be linked to directly?
My only salient comment is that his presence, and even voice, really strikes me as being much the same as Timothy Leary.
Just wanted to get that out there.
P.S. Rest In Peace Timothy Leary, William S. Burroughs, Hunter S. Thompson
-Clio
Karma: Bad (mostly from not giving a fuck)
Blog: http://clintjcl.wordpress.com
Quantum Networking: http://science.slashdot.org/article.pl?sid=04/08/3 0/0132204&tid=93&tid=126&tid=1&tid=14
and basically develop binary-networks for use as communications hubs between planetary bodies? (iow, a set of computers is developed, entangled, and one is sent to celestrial body, other remains on earth.
Opinion:=TMyOpinion.Create(Me);
you CAN NOT transfer information, but you CAN receive verification of receipt of transmission through this method. Hence, for Mars, this WOULD work, since the transmission time from Mars to Earth =~ 1333 seconds, but the entangled response would be instantaneous. Therefore, since the ceiling on TCP transmission is 2400 seconds, I do not see the problem.
Opinion:=TMyOpinion.Create(Me);
It depends on your ideas of the mechanism behind quantum entaglement whether or not the response is instant, the point is you can't detect any information from it. Pick up a popular science book on quantum mechanics, this has been covered many times. (Lindley's Where does the weirdness go is rather nice, and as it only covers the basics, being written ten years ago isn't a problem)