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Terabit-Per-Second Class Connections over FTTH
Big Fat Dave writes "Thanks to research from Japan's Tohoku University, an article at Tech.co.uk wonders if someday the megabit and gigabit classes of net connections will join kilobits in the 'antique tech' bin. By doing some advanced mathematics and 'tweaking' existing network protocols, researchers may be able to enable standard fiber-optic cables to carry data at hundreds of terabits per second. 'At that speed, full movies could be downloaded almost instantaneously in their hundreds. At the heart of the development is a technique already used in some digital TV tuners and wireless data connections called quadrature amplitude modulation (QAM). One glance at the Wikipedia explanation shows that it's no easy science, but the basics of QAM in this scenario require a stable wavelength for data transmission. As the radio spectrum provides this, QAM-based methods work fine for some wireless protocols, however the nature of the optical spectrum means this has not been the case for fibre-optic cables ... until now.'"
At that speed, full movies could be downloaded almost instantaneously in their hundreds
Not until the PC buses catch up..
Libertarian Leaning Political Discussion Forum.
We'll barely be up to 100 Mbit when the rest of the world hits terabit. The media conglomerates that own the rights to provide internet service to your home will make sure of that.
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...someone in MPAA just shat himself.
not in this country (us), would be nice though.
duh, what will it be used for? pr0n.
I can have my own copy of the Library o' Congress and let them worry about backup :)
Similarly, once you spent a few seconds downloading everything off the internet, what will you do next?
(3 seconds to download it, 25 years to read it all)
politicians are like babies' nappies: they should both be changed regularly and for the same reasons
I simply wan to know what "In their hundreds" means.
At that speed, full movies could be downloaded almost instantaneously in their hundreds.
This won't be as useful for Internet use (as mentioned above, the last link will continue to suck), but for businesses and other LANs with high demand (data centers, anyone?), this will be a big help.
You do not have a moral or legal right to do absolutely anything you want.
I'm not sure if this is the case still, but a networks teacher of mine told me some years ago that the bottleneck of the internet were the routers.
Truly, madly need this.
I get something like 70 NTSC channels and everything above oh 400 Mhz on my cable system is QAM 256. I believe the cable company trucks the signal over fiber (QAM and all) to a local node where it is converted to RF and split into the house..
How is this new or different?
Actually, this opens up some interesting possibilities for people like the RIAA and MPAA. When you can download a whole CD or DVD in seconds, there's no longer much point to someone who's system is connected, in having physical media, or even a copy of the media, on their own machine. Whatever type of business model they'd wind up with could take that into account, and they could come up with a Netflix-type model, or something new and appropriate to the new reality (when have they ever done THAT, though?) - pay $x/mo, or $x/mo/bitrate/resolution, or whatever. The online rental business could be huge.
... or not, your choice of colour, and a big honkin' net connection. Lots of RAM and a SSD boot drive, and something (magnetic card, keyfob, whatever, or nothing - just swipe your retina across a scanner or something) you can take with you to plug into whatever other machines you use to let that machine know it's you and to configure to your preferences. And nothing more. No moving parts other than the keyswitches and GP/CPU fan.
There's also the benefit of being able to do real-time offsite storage. The people who would care about needing massive amount of storage for their movie collection - no longer need to store their movies locally. Your whole machine could wind up being nothing more than an online access point with it being customized to be the HCI that you prefer: curvy keyboard (w/ or w/o lights) or not, big-ass widescreen display
This is the kind of technology advancement that can change almost everything in its field if enough people with vision can take advantage of it and work together to make it seamless.
multi-terabit connections are an absolutely wonderful thing to have in some academic research fields. Science research, computing research can all benefit. For some dude downloading movies and music? A 100mbit would be absolutely wonderful and gigabit would be more than enough.
Please let's not start that debate again. I know it started a long time ago with "no one needs an abacus, who's going to count over ten?" but please no more debating on what's sufficient and what's not as far as computing, etc. It comes up everytime there is talk of major increases in x aspect of computing. We don't need anymore of it.
http://greenobyl.com/ please.... think of the children!!
Just wait until someone with one of these gets Trojaned and the controller starts DoS-extorting Google.
"Screw Sun, cross-platform will never work. Let's move on and steal the Java language." - Visual J++ Product Manager
We need faster hard drives to catch up
The story is about doing it over fiber optics -- using an optical signal instead of an electrical one.
It seems like something that might be useful 20 years from now.
Quadrature amplitude modulation (QAM) is frequency based. It's 4 way (hence the 'quadrature thing) They're been doing way more than QAM in the last decade, they're doing 64-way amplitude modulation, with frequency spectrums (cable) for ages How the fuck are they using multi-frequency modulation techniques on light rays (fibre) ? This is either crap, very good or deserves a Nobel prize! Is this an early April 1st ??
Do we need terabit connections (TCP or whatever)?
I don't know, do we? Listening to the telcos and cablecos complain about how they have to throttle everyone down to a small percentage of the advertised speed in order to make sure there's enough bandwidth for their precious, precious video and voice services, the answer seems to be yes.
Too bad they'll have nothing to do with this technology. It's far more profitable to hold everyone hostage than to shell out the billions in capital to upgrade the network.
If its "Terabit-Per-Second Class Connection" I wonder what a first class connection gets you.
Just watch, first person to get one of these connections will be the head researcher's mother.
"Actually, this opens up some interesting possibilities for people like the RIAA and MPAA. When you can download a whole CD or DVD in seconds, there's no longer much point to someone who's system is connected, in having physical media, or even a copy of the media, on their own machine."
I see that slashdot needs a constant reminder that a lot of people can't even get a decent dial up connection let alone broadband. The threat to their business model isn't more people getting this tech but the preexisting base abusing it even more.
"Whatever type of business model they'd wind up with could take that into account, and they could come up with a Netflix-type model, or something new and appropriate to the new reality (when have they ever done THAT, though?) - pay $x/mo, or $x/mo/bitrate/resolution, or whatever. The online rental business could be huge."
The piracy problem isn't a distribution problem, or a storage problem. It's getting people conditioned into believing if it's on the internet it must be free to start paying. Technology isn't going to fix that social problem.
"There's also the benefit of being able to do real-time offsite storage. The people who would care about needing massive amount of storage for their movie collection - no longer need to store their movies locally."
That's a funny position for paranoid slashdot to take.
"This is the kind of technology advancement that can change almost everything in its field if enough people with vision can take advantage of it and work together to make it seamless."
The development is overseas but the US is the country that's going to cough up the capital to make it commercial.
A horse can't be sick, you know, even if he wants to.
And any half brained AC would spend three seconds using google if s/he didn't already know. FTTH = Fiber to the home
http://www.google.com/search?q=ftth
appleguru.org
If you step over the top sekrit 10TB monthly limit the provider will cut you off and send over the company dog to scoot its anus across your new carpet.
To get a TB/s - 10 Terabits/s (1/10th or less of what they claim) implies you have gates that operate at better than 0.1 pico-second reflex times (that is, off-on-off). I am only talking the receive buffer. I can see what you could do with all the new cores now - make them into a parallel IO where each takes a time slice of a microsecond or so, that is, a megabyte of data, oh wait, we can't do cache writes that fast currently. Looking at the article and tech I see a bunch of lambda's and a lot of parallelism and nowhere near the speeds given for a long time, and totally different IO channel tech. On the other hand, I can see types of this tech being used at lower speeds all over. The high speed they give is really a red herring.
Fiber To The Home, it's actually an old acronym, as is FTTC (Fiber To The Curb). Now they use Fiber To The Premises (FTTP) and Fiber To The Neighborhood (FTTN)
:)
Any self respecting geek would know that
In the US It's a pipe dream for anyone not currently a Verizon customer. As much as I dislike Verizon for doing crap like crippling their cell phones, at least they modernize their networks. I unfortunately am in a Qwest zone, so I will see it either when Verizon buys Qwest or when hell begins its second ice age (so never or never and a day).
When I see my adsl is actually 1.5MegaBit p/s down, 0.256 mbps up for 38$ per month... :(
Sad day for me.
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The article linked doesn't mention fiber to the home at all, it seems it was a bit of embellishment on the part of the slashdot story poster.
The article doesn't say whether the new advancement was for singlemode or multimode fiber (or both), but given that singlemode fiber has maybe a thousand times the data capacity at distances of 100km that multimode has at distances of 2km, I suspect they are using singlemode.
I'm not certain, but I also suspect that most FTTH installations are multimode (it's easier to work with, and the equipment at either end is cheaper); if so, this new technology really doesn't apply to FTTH.
"The very last thing they want is for it to be as quick to download movies as it currently is to download music."
From the standpoint of piracy I see their point. From the consumer standpoint getting ones movies faster really doesn't help. You still have to watch it in real time. So now you have a bigger pile of movies to go through and only so many hours in a day.
The way a lot of telco hardware gets around the limitation that no computer exists that's fast enough to process the full available throughput, is that the connection is split into hundreds of separate channels, each one on a separate wavelength. A particular router interface need only deal with one channel, not all of them at once. (A single channel might be an OC-192, which runs about 10 gbps.)
The channels are combined and split apart by a dense wavelength division multiplexer; I don't really know how they work, but if you think of it as an expensive prism you're probably not far off.
I can remember when kilobit/sec connections were something to look forward to. I traveled three years (early '80s) with an acoustic coupler that could often communicate back to the office only at 300 baud (and periodically error out at that speed). Usually, I wanted to use 3270 emulation over the connection. This is like watching paint dry only more boring. It did have occasional redeeming value, however. Watching the emulated 3270 data stream slowly displaying itself on the screen was a great way to visualize where data streams were miscoded!
What is routinely done today in hybrid fiber/coaxial cable (HFC) cable TV systems, is to use linear RF-band, often 50-750MHz in 6MHz (North American standard) bands corresponding to television channels. Both 64- (6 bits/baud) and 256- (8 bits/baud) QAM modulation standards are used. 64-QAM has been around since maybe 1996.
256-QAM requires a better signal/noise ratio through the transmission path, and better A/D resolution and more demodulation work in the receiver. 256-QAM gives around 38.8Mb/s payload rate after subtracting TV standard (ITU J.83B) ECC and packet overheads. 256-QAM is seeing increasing use as better chip technology makes the demodulators cheap, as cable plant is upgraded to push fiber farther out toward the end subscribers with better signal quality.
700MHz / 6MHz = 116 TV channels * 38.8Mb/s = roughly 4.5Gb/s digital capacity for QAM on a 700MHz RF bandwidth. Again, this is done routinely today, except of course a TV receiver only selects and demodulates a single 6MHz channel at a time.
One could WDM a number of 700MHz RF ensembles onto a fiber, but this of course requires source lasers (ones designed for wideband linear modulation, or with $$$ external modulators) with precisely tuned and stabilized wavelengths, and corresponding optical splitter/filters, individual optical receivers for each wavelength, and RF-band demodulators for however many channels the RF band has been divided into.
Terabit through this conceptually straightforward WDM approach would require over 200 such optical carriers (a couple of racks of very expensive equipment. It's feasible, but not something you will have on the side of your house (even receive-only) in the near future.
Sorry but as long as I cannot access the actual article I have to assume is fake.
This is science: convince the world!
So putting your actual paper behind some login is a no-no.
The economics of running an online service will also change. As bandwidth costs on the backbones are lowered, it will become more feasable for smaller companies to provide bigger data services. This means things like youtube could easily go high definition, setting up your own audio stream service might actually be really cheap, and personal online storage of gigabytes of data transfers could also be possible and cheap.
It will be interesting to see the progression of data technologies. Long ago we used floppies to store our documents. Just ten years ago we had decent sized hard drives and cdroms/dvds. Today we now use flash memory and portable hard disks. If backbone tech keeps increasing in capacity we'll eventually just forget physical mediums and throw everything onto a server somewhere and reconnect to the internet (probably from some wireless connection) to retrieve and store most of our data. Software distributions and installations could go totally disk-less (boot off the network somehow?) and you might just start streaming your music collection off of an internet storage server. Many different technologies are required to get there but as the barriers keep dropping it will quickly become a reality.
Are you aware that "radio waves" and "light rays" are fundamentally the same thing?
<Massive generalization> anything we have worked out how to do "with radio" is something that there is no fundamentally intrinsic reason why we should not (one day) be able to work out how to do "with light"</Massive Generalization> (and don't bother saying things like passing 'radio" through a sheet of cardboard which obviously blocks "light" - I'm talking about *uses* ie modulation/signalling techniques, not "modifying the laws of physics" issues)
Or do you think that a 1kHz audio wave is in some *magic* way fundamentally and intrinsically different from a 5kHz audio wave? or a 25kHz wave?
Visit CryptoGnome in his home.
Or lots of really cheap disks. There's already RAID which takes multiple disks and combines them to improve performance and redundancy. There's also ZFS which does the same thing but in software, and it makes managing large sets of disks simpler. At a larger scale you can start exploiting P2P methods where every peer contributes a small amount but when you put together the pieces it adds up big time.
It looks as if
http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumber=4348615&isnumber=4348298
is something like the work being reported on; 'A 1 Gsymbol/s, 64 QAM coherent signal was successfully transmitted over 150 km using heterodyne detection with a frequency-stabilized fiber laser and an optical phase-locked-loop technique. The spectral efficiency reached as high as 3 bit/s/Hz.'
Masato YOSHIDA's list of papers at
http://db.tohoku.ac.jp/whois/Tunv_Title_All.php?&user_num=LTU0OA==&sel1=1&sel2=1&sel3=1&sel4=2&page=1&lang=E
looks very plausible in the context of this work; 'coherent optical transmission' is I think the relevant buzz-word. Going from 1Gsymbol/s to 10Tsymbol/s is clearly a lot more work, but being able to do optical QAM at all is pretty spectacular.
http://mobile.slashdot.org/article.pl?sid=07/11/16/1326214
I am not savvy about this stuff. Could this be the "stable wavelength" referenced in the article?
Yeah, it's compensation. When you have something new, someone'll find a use for it.
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I have Verizon's fiber optic service, which according to wikipedia is single-mode as well, so maybe I'm wrong and most FTTH installs are single mode. That would be a very good thing - no one's going to need to dig up that fiber for at least thirty or forty years (and maybe hundreds), assuming there aren't silly bottlenecks somewhere in the system.
No, it's not the same because the cable company isn't don't QAM over Fiber, they're doing over... wait for it... CABLE. They may be moving the data around over fiber before it gets to your house, but that fiber optic connection is the fiber equivalent (in terms of modulation techniques) of the old 1 megabit co-ax. In fact, QAM is what allows that crappy co-ax connection that the cable company STILL uses to push video and internet up into the 10 - 20 megabit range.
;)
Apply that same tech to fiber, guess what? those 10 gigabit single-fiber connections suddenly reach terabit range.
Copper technology is nearly maxed out. If it ever hits the 100 megabit range like has been promised by some researchers, it WILL be maxed out. Fiber optics are still in the toddler stage of their developement, and if they can get QAM to work it'd be like jumping into the teenage stage.
You know, wild and rebellious.
Drop a hundred bucks on a telecom manual if you really want to know what's going on with all this stuff. As a bonus it's excellent if you're having trouble sleeping. 10 minutes and you'll be out like a light.
Cheers!
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
Of course those bitrates are theoretically possible with optical fibers. After all you could apply the advanced modulation schemes of DSL to them, theoretically.
Actually right now for short distances the dispersion might be small enought to actually do QAM, but I don't believe it's feasible on longer lines.
Of course once we get ways to use lightways in the same way as radio waves it all would be simple, but right now, even the best lasers still actually produce band-limited noise with a bandwidth of a few hundred megahertz. A detector can only take a chunk of the spektrum and just give you the intensity of the signal. Comparing this to radio, we still are in the 1920s, perhaps earlier.
I didn't even think about ultra HD video confrencing, but rather downloading static movies. Uncompressed, raw streams like you're describing definitely would require many hundreds of gigabits per second. However I have yet to see cheap ultra-ultra high res HD webcams on the market yet that would demand these kinds of insane speeds at a consumer level. However, the future is coming fast, and I'm sure high-res webcams of that kind will be here soon enough. :)
At this moment I don't think home users would benefit from a connection faster than 1 Gbps.
I have a gigabit connection at home and I can download a DVD in less than 1 minute and it's not even getting close to reaching the limit of my connection. The hard-disk is getting overloaded at about 20MB/s in BitTorrent.
You can watch streaming BluRay DVDs with a gigabit connection so unless we come up with some way of producing a lot more data for entertainment purposes, the terabits-per-second connections will be overkill for any average user in the near future.
Point 1: We have been using QAM in 56k modems for years. Point 2: There will have to be alot of infrastructre work done before we get the required singlemode fiber to my house. It won't hang from a power pole, every slight bounce and swing of that cable will induce phase noise (bad news for QAM). Buried cable will just love earthquakes!
What is an audio wave? You mean sound wave, which is a compression wave, which is nothing to do with em.
If you're reading /. and you don't know WTF FTTH is, IMHO it is IYBI to RTFM before a BOFH applies a LART. THBS, IANAL so YMMV.
OMFG that is a lot of p0rn.
Once backbones get upgraded, we will see a sub-second slashdot effect.
Usage: km/h for speed (kilometers per hour); kph for very slow impulses (kilopond hours).
(sigh) WHY do I need to explain EVERYTHING? ..... an "audio wave" is the same moronically stupid term as "radio wave", and I was using the term in an example - if we (collectively, the human race) are capable of understanding that "sound waves" at 1kHz are not fundamentally different to "sound waves" at 5kHz then FOR $RANDOM_DEITYs SAKE WHY do we mystically believe that two waves in the electromagnetic spectrum are *fundamentally* different purely because one is higher frequency than the other.
Visit CryptoGnome in his home.