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.'"

ya but..

[mastershake_phd (1050150)]

At that speed, full movies could be downloaded almost instantaneously in their hundreds

Not until the PC buses catch up..

Re:

[ceeam (39911)]

No "PC"s on "backbones" I think.

Re:ya but..

[gad_zuki! (70830)]

>No "PC"s on "backbones" I think.

Then no terabit connection for you. I dont care how fast the backbone is. Where I live the last-mile technology is DSL which for my location maxes out at 1.5mbps.

I think the "OMG LOOK HOW FAST TIS IS" kiddie-mentality of movies-per-second ignores the whole issue of last-mile distribution. And PC buses. And practility. And economics.

Youd think slashdot would have better things to post than PR releases.

Re:ya but..

[Kjella (173770)]

The practicality and economics is that in all larger construction projects here in Norway today, whether it's apartment blocks or new fields of housing they lay fiber connections. There are approximately two million households and about 150,000 (7,5%) of them can get fiber connections. Each year 30,000 new houses are built and many of them will have fiber connections, though lone houses don't qualify. If we say 25,000 a year (30,000 less lone houses plus retrofits) then over the next decade I expect that to rise to 150,000 + 10*25,000 = 400,000 (20%) for a conservative estimate. Oh yeah and we're considerably more sparsely populated than the US. Fiber has good end-mile economics as long as you're putting down cables anyway. Now, that wouldn't make it useful with a terabit last mile but if you want real capacity and not US "unlimited" capacity, then it's really nice if actually delivering is very cheap. And a few thousand people on gigabit connections add up to terabits quite fast...

Re:

[evilviper (135110)]

Where I live the last-mile technology is DSL which for my location maxes out at 1.5mbps.

So because it won't specifically affect your internet connection, it isn't news?

I think the "OMG LOOK HOW FAST TIS IS" kiddie-mentality of movies-per-second ignores the whole issue of last-mile distribution.

FTTH is last-mile distribution.

Re:

[rts008 (812749)]

Or my favorite metric:
http://www.nakedworldrecords.com/phone.htm [nakedworldrecords.com], but I'm having trouble concentrating on calculating the bandwidth involved.

Re:ya but..

[Ogun (101578)]

Fastest backbone router that I know of is the Cisco CRS-1. It can scale to a system capacity of 92 Tbps in total, using 72 42U rack units as one large router. Still, the fastest interfaces on that machine is OC-768 at roughly 40 Gbps.

Re:ya but..

[funkboy (71672)]

Probably because you haven't seen a Juniper T1600 [juniper.net]. It has 2.5x the per-slot bandwidth of the CRS-1. The Cisco marketing literature may go to 92tbps, but I challenge you to show me a production CRS multishelf system with more than one fabric shelf. Once T1600 modules are available for the TX Matrix the system will provide 6.4tbps in two and a half racks, using far less power than the equivalent real estate worth of CRS hardware (2.4tbps max), at about the same cost. BTW a fully configured 72-rack CRS-1 would require about .8 megawatts of power and belch about 2.5 million BTUs of heat per hour...

Erm, not that that's a biased viewpoint or anything (heh)...

Anyway, IMHO far more important to router scalability is the per-slot and per-watt bandwidth, not how many systems you can chain together (as long as you can chain some reasonably useful number, but I don't see a need for more than 8 chassis in a system). The CRS-1 won't be able to handle 100gE without a system-wide fabric upgrade or double-width cards or something. The T1600 (and for that matter, the Foundry NetIron X series, though not in the same class of capabilities or scalability as the Juniper) will be able to slot in 8 100gE linecards the day they're available.

separate channels

[j1m+5n0w (749199)]

True, but the routers and repeaters on the backbone have buses don't they?

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.

Re:

[funkboy (71672)]

> True, but the routers and repeaters on the backbone have buses don't they?

The 750hp 2.4L V8 engine in an F1 car produces about 3-4x the amount of power of a production car engine of the same displacement, but you don't see even high-end mfrs like Porsche putting that sort of thing in street cars (for reasons I hope I don't need to explain).

The data plane in high-end routers have custom-designed switch fabrics [wikipedia.org], which technically are not buses and operate in a different (more scalable) fashion. The wiki

Yeah, but in the U.S.

[dgatwood (11270)]

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.

Re:

[ScrewMaster (602015)]

The media companies (well, the motion picture companies) will do everything in their power to prevent it. All they have to do is have Congress or the FCC keep the telcos in power and we'll never see anything more than we have now. The very last thing they want is for it to be as quick to download movies as it currently is to download music.

Re:

[ScrewMaster (602015)]

True ... but the media outfits aren't as rational about it as you are. I mean, they've already shown that they're more than willing to throw all of us into the fire as long as they get what they want. Besides, I don't believe that the bang I get for my ISP buck should be limited to what is acceptable to a bunch of self-serving corporate entities, most of whom aren't even U.S. companies anyway! Incredible.

But you're right though. As the economy continues to worsen and Americans are being forced to work ha

Re:

[x_MeRLiN_x (935994)]

You're talking rubbish. ADSL+ was being sold to UK subscribers over two years ago. I don't see why anyone should be blamed for the fact that where you live isn't populated enough to be deemed profitable yet. ISPs are not charities.

http://www.pcpro.co.uk/news/77057/uk-online-joins-24mbps-adsl-rollout.html [pcpro.co.uk]

Re:

[x_MeRLiN_x (935994)]

My point was, no, it's not just Central London and Manchester. Two years ago, yes - but not now. You're suggesting that the trials failed and LLU has ceased - or that ISPs have done absolutely nothing in that time?

I live in Kent and 24 Mbps is most definitely available - but I have 20 Mbps from Virgin.

Re:

[lattyware (934246)]

Your 20mbps is from Virgin. Who do cable. In a lot of, nigh most, areas you cannot get cable, and most areas do not have lines that can handle high speed connections. My point was that most areas will not get those kind of speeds, that is true. I did not suggest it was ceased. I suggested that not everyone is going to get those speeds for quite some time.

Re:

[vidarh (309115)]

You stated "Yes, you can get that, but only in Central London and Manchester," which isn't remotely true.

I bet...

[ceeam (39911)]

...someone in MPAA just shat himself.

the vision

[Tumbleweed (3706)]

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.

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 ... 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.

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.

Re:

[vivaoporto (1064484)]

Not really. My cable TV provider (that is not a MPAA member, but certainly buy a lot of content from them) would love such technology in order to serve digital Video on Demand faster, less compressed and to more people at the same time. As other people observed, such a fiber would be next to useless to current home user technology (other components would become the bottleneck), but to content provider, it would be miraculous.

Finally

[djupedal (584558)]

I can have my own copy of the Library o' Congress and let them worry about backup :)

will need bigger hard disks

[petes_PoV (912422)]

every time connection speeds have increased (300 Baud, 1200, 56k, .... 20Mbps) you've needed more disk space to store the cr... you download. At Tbit speeds, where will you put all this?

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)

Re:

[hjf (703092)]

maybe this will make the Network Computer dream a reality? Imagine that you have an internet connection that's faster than any drive array you can make. Then add Web 3.0 apps to it. No more formatting, upgrading, antivirus, whatever. Maybe for us geeks that would be too much, but for Common People, that would be practical. Pay-per-use computing. It would be a service just like cable TV.

Re:

[Kegetys (659066)]

> At Tbit speeds, where will you put all this?

in /dev/null

LANs

[Sarten-X (1102295)]

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.

Aren't routers the bottleneck

[iampiti (1059688)]

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.

Re:

[porpnorber (851345)]

So you need 8 Mbit or so superjumbograms. In principle, not a problem, though some header fields need to be widened. The issue becomes one of memory bandwidth, instead: that's a fearsome hose, by today's standards.

Hasn't the cable company been doing this for years

[NuttyBee (90438)]

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?

Botnet, anyone?

[Myria (562655)]

Just wait until someone with one of these gets Trojaned and the controller starts DoS-extorting Google.

Re:Hasn't the cable company been doing this for ye

[Kohath (38547)]

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.

The data has to go somewhere...

[normalperson (552607)]

We need faster hard drives to catch up

Re:

[Frozen Void (831218)]

Its the year of Solid State Disk on the desktop.

QAM

[b1ffster (628989)]

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 ??

Re:

[j1m+5n0w (749199)]

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 ??

Light is just another medium for transmitting a signal, why should it be any different? The only reason I can think of why they might not have done this earlier is that it's hard to do elaborate signal processing at the speeds they want to use.

Re:

[niceone (992278)]

Quadrature amplitude modulation (QAM) is frequency based. It's 4 way (hence the 'quadrature thing)

No, the quadrature thing refers to the two carriers being 1/4 of a wavelength out of phase. You can have any number of different symbols and it is still QAM: http://en.wikipedia.org/wiki/Quadrature_amplitude_modulation [wikipedia.org].

I'm not quite sure what the break though here is, and TFA isn't that clear, but I Wouldn't write it off.

Re:QAM (how to fail physics 101)

[Crypto Gnome (651401)]

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) ?

Are you aware that "radio waves" and "light rays" are fundamentally the same thing [wikipedia.org]?

<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?

Whoa

[NIckGorton (974753)]

If its "Terabit-Per-Second Class Connection" I wonder what a first class connection gets you.

Just You Wait

[riffzifnab (449869)]

Just watch, first person to get one of these connections will be the head researcher's mother. [slashdot.org]

Throughput is only part of the experience

[Sponge Bath (413667)]

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.

Disturbance

[FridayBob (619244)]

At that speed, full movies could be downloaded almost instantaneously in their hundreds.

At Slashdot, readers sensed a great disturbance in the Force, as if millions of movie studio and record company executives cried out in terror and were suddenly silenced.

Showing my age

[Mostly a lurker (634878)]

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.

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 hav

Useless cheerleading articles

[dsgrntlxmply (610492)]

Neither this article, nor anything linked from it and accessible without subscription, describes the result in any useful detail.

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

Some relevant references

[Tom Womack (8005)]

It looks as if

http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumber=4348615&isnumber=4348298 [ieee.org]

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 [tohoku.ac.jp]

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.

Academic work

[Bananatree3 (872975)]

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.

Re:Academic work

[porpnorber (851345)]

You go over the 1G mark just by doing uncompressed HDTV, and uncompressed is good; for teleconferencing applications, codec latency is the killer, since your brain is hardwired with estimates of other people's response times. Now, you may think that HDTV is good quality, but if the future offers me 64Mpixel HDR images in stereo (or better, with full depth representation) at 100fps, I for one am not going to complain. Multiply it out; that's approaching the terabit per second, and I didn't even have to choose any outrageous numbers—2*8k*8k*3*16*100 is pretty conservative for a convincing virtual French window. Contemporary video, even HDTV, is not enough like being there, as you come to realise once you've had a chance to play with high-end systems (my stuff: http://ultravideo.mcgill.ca/activities.html [mcgill.ca]; my friends': http://www.hp.com/halo [hp.com]; both a few years old by now).

So, yeah, what you really want the terabit network to your home for—is chatting with your mum.

I wish I could show you even current research teleconferencing systems in operation... and they suck compared to what I'd like to be doing.

(I'm not, by the way, suggesting that there are no useful low-latency techniques providing moderate compression for when you don't have gigabandwidth—of course there are. I'm just pointing out that these numbers are not unimaginable, and that if the pipe were provided, there would indeed be end-user applications for it.)

Re:Nice, but what for?

[stormguard2099 (1177733)]

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.

Re:

[ceeam (39911)]

Web-apps, terminals... Universal streaming of TV, radio, phone, etc signals over IP. You're like an IBM rep in the 50s about 5 computers being top for the world.

Re:

[appleguru (1030562)]

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 [google.com]

Re:

[Creepy (93888)]

Fiber To The Home [wikipedia.org], 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 i

FTTH=fiber to the home

[j1m+5n0w (749199)]

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