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BT and Alcatel-Lucent Record Real-World Fibre Optic Speed of 1.4Tbps In the UK
Mark.JUK writes "The United Kingdom's national telecoms operator, BT, has successfully teamed up with Alcatel-Lucent to conduct a field trial that delivered real-world data speeds of 1.4 Terabits per second over an existing commercial-grade 410km fiber optic link. The trial used a 'record spectral efficiency' of 5.7 bits per second per Hertz and Flexgrid technology to vary the gaps between transmission channels for 42.5% greater data transmission efficiency than today's standard networks. The speed was achieved by overlaying an 'Alien Super Channel' (i.e. it operates transparently on top of BT's existing optical network), which bundled together 7 x 200Gbps (Gigabits per second) channels and then reduced the 'spectral spacing' between the channels from 50GHz to 35GHz using the 400Gb/s Photonic Services Engine (PSE) technology on the 1830 Photonic Service Switch (PSS). It's hoped that this could help boost capacity to those who need it without needing to lay expensive new fiber cables."
That's about 875 micro-library-of-congresses per second, assuming 600 dpi LOC digitization. Getting close to breaking the coveted milli-LOC/s barrier!
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Did Gene Roddenberry get the naming rights to all of the equipment ?
Nullius in verba
Yeah, except it takes a blazingly fast line and makes it even faster. At this level of aggregation no single customer is going to notice much, you rarely hear people who have a big last mile pipe complain about the backbone speed. Nice to see the backbone keeping up with FTTH and such, but really the main issue is that fiber is still for the few. Or to turn on gloat mode, I'm not sure what's behind my 100Mbps pipe but it seems pretty damn fast to me.
Live today, because you never know what tomorrow brings
Just you wait, they'll raise all speeds to that, but then slap a datacap of 500MB on it.
, in LOCRiDS ( Library Of Congress Replacement Cost in DollarS ) , of one of those to my doorstep ?
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
The GHCQ and NSA thank you for filling their files faster.
Yes, modern fiber is becoming very DSL-like, with many sub-carriers and advanced encodings for each carrier. Unfortunately the power requirements are fairly high.
Finally! A year of moderation! Ready for 2019?
Where did you learn math? Fox news?
Quotation needed.
BTW, most people are on GPRS/3G/whatever - but you probably meant 'landline' type of connectivity. I really doubt that there are more people using dialup compared to low-speed DSL (1-2Mb range).
If only they could have such speeds over wireless connections...
I can't see people who live in areas that are hard for cable to reach benefitting much from this.
Deal with reality - the world as it is - rather than ideality - the world as you would like it to be.
Once the government has finished fucking up our Internet access completely.
real-world data speeds of 1.4 Terabits per second over an existing commercial-grade 410km fiber optic link.
Meaning the link can store only 1.4 Tb/s * 410km / c = 239 MB. (Where c is the speed of light in the fiber link).
Bah, that's nothing.
If Pandora's box is destined to be opened, *I* want to be the one to open it.
Let's say it's Sunday evening and Netflix is getting choppy. How would you even know if the problem is the last mile or backbone?
The difference is that DSL is running data over old Cat 3 voice grade lines, and there is a clear technological benefit to moving to an alternative media for distribution. The reason is noise: Cat 3 was never designed to reject it. Coax, Cat 5, and other wire types were specifically engineered to help reject noise at different frequencies. And the better the category of wire, the better the throughput.
Fiber doesn't generally have that same kind of problems (unless you foolishly installed cheap plastic optical fibers.) There isn't a special "greased lightning fiber" people can turn to that carries more data. Instead, advances in lasers, optics, and encoding technologies are used to increase throughput by replacing the transmitters and receivers.
In general, if you need more throughput in a fiber environment than commercially available transmitters can produce, your only choice is to pull more fibers. Whereas in DSL-land if you need more throughput, the rational choice is to abandon the technology completely and move to a different media.
John
Trace route or pathping?
Speak for yourself - I just picked up a $5000 S/PDIF cable from Monster Cable that moves those bits so much faster than any other cable on the market. When you hear the results, you can just tell that the 1's and 0's have so much more definition and crispness than ordinary commodity cables.
I don't think they're effective for that purpose, at least not any more. The actual structure of a network within each ASN is obscured (for network security and business propriety). And latency may well depend on the content of an individual packet, where it's to/from, whether it's part of a stream, etc due to traffic shaping.
(bit)/(s)/(Hz) = (bit)/(Hz)/(s)
CLI paste? paste.pr0.tips!
Most ISP don't actually shape Netflix, they use DNS to send you to a different server to alter your route. Shaping can happen, but you find it more in ISPs that have 1mb DSL, not 100mb cable. It gets really hard to shape large numbers of people with fast connections. If they are shaping, not much you can do. My ISP does not shape or QoS, so tracert and pathping work fine.
Monster cables, making sure the super-position of your photons are kept pristine.
Speak for yourself - I just picked up a $5000 S/PDIF cable from Monster Cable that moves those bits so much faster than any other cable on the market. When you hear the results, you can just tell that the 1's and 0's have so much more definition and crispness than ordinary commodity cables.
I hate to disappoint you, Skippy, but that's just regular optical fiber that's been SpeedWaxed. You still need to buy a tube of Denon Optical Fiber SpeedWax and coat the fibers monthly. Otherwise, the ones tend to get a bit fat, and the zeros get a little skinny. Without it, the highs will have a pronounced distortion on the even harmonics, and the phrenological ephemera will subluxate the transception. Oh, and don't forget to get their Shielded optical cable, specifically designed to reject RF interference. Get the one with gold plated connectors to ensure rich bass.
John
You've forgotten that the Hz represents cycles/s, not just 1/s. Hence their so-called "spectral efficiency" is 5.7 bits/cycle. The problem of course is that the article does not address the SNR nor the BER that it took them to get that 5.7 result. If you need cryo-tech photodetectors and massive FEC to get that result, it's less impressive than doing it with the existing kit and minor data redundancy.
Oh, I'm sorry sir, I thought you were referring to me, Mr. Wensleydale.
No, [Hz] = [1/s]. Or put differently, the 'cycles' you mention is unity
CLI paste? paste.pr0.tips!
Although noise rejection isn't normally an issue, different fibres do have different bandwidths:
http://en.wikipedia.org/wiki/M...
http://en.wikipedia.org/wiki/S...
and then there's the hollow fibre mentioned in the article, which achieved 73.7 Tb/s!
I have never let my schooling interfere with my education. - Mark Twain
There are multiple different types of optical fibers out there and not all of them are suitable for DWDM, polarization and various other schemes... so "greased lightning" fiber does exist if you compare fiber from ~30 years ago with state-of-the-art specialty fiber.
As for fiber not having the same problems as DSL, most of the electromagnetic stuff that applies to DSL also applies to fiber; just on such drastically different scales that they become negligible in most cases.
I hear plenty of people complaining that their real world throughput at peak times is much lower than their sync speed. That means that either the servers or some part of the network between the user and the server is overloaded.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
That's why I qualified my comment with "generally". Figures I'd get caught :-)
John
Lest you think I was kidding about shielded fiber cable with gold plated connectors: http://www.amazon.com/Cable-Ma...
But it's only $8.99, so it's kind of difficult to mock it mercilessly.
John
I would be happy if BT could give me the off peak speed I can get during the night of 73Mb/s during peak times where it drops to 8 - 10 Mb/s.
Well as your copper from your house to the cabinet can do 73mbit, increasing bandwidth on the second-to-last mile from cabinet to linx is the only solution.
Fortunately thats exactly what this technology promises.
Wikipedia says the record on an optic fiber is 101 Tbps. How is this better?
I had this problem for about a year with Virgin Media. Turned out to be their Content Delivery Network, i.e. the caching servers inside their network. Blocking them at the router level fixed the problem.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Pffft... 100Mbps? My PHONE gets 150Mbps in both directions. Home broadband is 1000Mbps over fibre.
My ex had 100Mbps fibre back in 2003, for about 23 quid a month. It was more common back then than it is in the UK now. We are over a decade behind thanks to BT.
http://i.imgur.com/9dZfFQk.jpg
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC