
My hat is off!
Australian scientists say they have broken data communications speed records by shifting 44.2 terabits per second over 75km of glass fiber from a single optical chip. The five-by-nine millimetre prototype gizmo is described as a micro-comb in a paper detailing its workings, published in Nature Communications on Friday. Light …
If you were lucky enough to get the original FTTP/FTTH you can do around 4Gbps on current plans, capable of so much more currently, tack this on at either end and you have such fast speeds you end up in enterprise areas much easier and cut out the middle-men.
Besides Australia makes a ton of money each year off our patents with Wifi, this'll be something else the govenrment can fire the inventors of then use the profits to help rugby.
It's not just DWDM on a chip, it's OFDM on a chip. The carriers can be much closer together relative to their bandwidth than on DWDM as they are all coherent and have a well defined distance. Essentially the neighbouring frequencies will interfere with the middle one, but those interference patterns will cancel themselves out over a symbol period.
Honestly I do not think this will require a lot of rack space. After all this is "just" 422 times as much as already established 100 Gbit/s and this can apparently is compatible with CMOS, so you could even place your routing logic on the same piece of silicon.
“We used a next-generation optical modulation format with 500 gigabits-per-second per wavelength. With the 80 micro-comb wavelengths, this combined to form an optical super-channel, which added up to 40 terabits per second,” Corcoran said.
Honest question: how can they achieve 44Tbps with 80 500Mbps wavelengths? Arithmetic didn't change, AFAIK...
You're missing the point. The fibre they're using is in the ground already. The cost of the system was never the cost of the fibre nor electronics, it was the cost of digging the trench. Everyone, forever, knew the potential bandwidth of single mode fibre but lasers, in 198x, were a bit rubbish and detectors were not amazing either. But back to the trench, stick a dozen fibres in the ground even though you don't need eleven of them, because you don't need to dig a second trench and leave dark fibre there because you didn't know how fast Tx/Rx was going to improve. Research on Wavelength Division Multiplexing was also going on in 198x, but in to give a comparison in those days line width on VLSI was in 10s of micrometres.
"You're young, aren't you?"
Note "per session". For the young the repeat interval can apparently be very short. Not sure what is claimed as a record. IIRC The Kinsey Report did have some double-digit*** numbers per day for what was considered the male capability peak circa age 16.
***not necessarily double-finger
The University of SMUT is currently working on a porn AI, and they are optimistic that their program will be able to generate any and all customisable flesh combinations with associated grunts and groans to fool anyone into thinking it is real.
This program, once installed on a PC, will free up 90% of the internet and reduce the instances of PC infection to almost zero.
Actually it is ideal for home broadband now! as long as the cabling is good probably wont be any need to replace the system for the next 100yr or so. Mind we hate that type of thinking in government projects, why make something to last when we can have lucrative maintenance contracts to put out to tender each year or a system we can upgrade every few year.
The issue isn't so much getting enough data in -- there are already switch chips with 25Tb/s capacity, with 50Tb/s coming in the near future -- as what happens to the optical signals. Optical transport networks rarely treat the whole fiber bandwidth (>40THz) as one point-to-point pipe (one massive "superchannel"), they use ROADMs (Reconfigurable Optical Add-Drop Multiplexers) to route different wavelengths to different destinations. The closely-packed signals of the "optical comb" approach can't be used for this because you need guard bands between the channels to allow them to be separated and recombined -- and also they don't all come from the same source.
There are parts of the OTN system where one fat pipe crammed with data is all that is needed (e.g. undersea links of several thousand km) but these are only a tiny fraction of the total installed hardware, far more is used for shorter links within countries and continents and these all use ROADMs.
There are also issues to do with yield and reliability when you integrate so many optical channels into a single device.
So it is an impressive technical achievement, but don't think it's going to completely transform the world ;-)
“ There are parts of the OTN system where one fat pipe crammed with data is all that is needed (e.g. undersea links of several thousand km)”
RFOG is often used in long distance transmission as the signal can be amplified several times before it needs to be recreated.
This new technology is not for long haul transmission. Its core, site to site & transmission And will enable faster edge.
This new technology is not for long haul transmission. Its core, site to site & transmission And will enable faster edge.
I guess this is where pricing will come in. On shorter distances, infrastructure owners may already have 144f of 288f cables and the ability to run more in their ducts. So potentially cheaper to just light another fibre. And possibly less risky, ie 44Tbps of credits vs 25Tbps in an outage. I guess it could be handy for data centre replication/backups where DC's are 50-75km apart, or of course for academic networks where they're generating collosal amounts of data, ie the benefit if it being wider, not 'faster'.
Staggering - I was impressed when I started work in 1970 and we were squeezing 960 telephone channels down a 4 MHz coaxial cable! Then we got 30 channels down an ordinary telephone quad and the rapid expansion of digital comms began.
This development just shows how innovation can continually improve the things we thought were already at "maximum smoke"
"Staggering - I was impressed when I started work in 1970 and we were squeezing 960 telephone channels down a 4 MHz coaxial cable! "
Aah - you're of the same era in the telecommunications business as myself (I started in 1972, retired October last year).
The good old days, when a supergroup was massive capacity and digital communications meant a VF telegraph system running at 30 baud.
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"at the risk of being quoted forevermore"
It's a given for any statement of an absolute limit. Even quoting "The Laws of Physics" when referring to latency might not hold true if quantum effects are able to be exploited to exceed the transmission speed of light.
There is a quote along the lines:
"When an expert says something can be done - then they are usually right. When an expert says something cannot be done - they are likely to be proved wrong eventually."
Parkinson's Law is immutable: "Everything always expands to use all the available resource".
Oh, but it is far.
They will remodulate every 40 km, usually a lot less. Even the sea cables remodulate at less than 40 km (I remember each 10 km, but I'm not sure).
Check that table on German wikipedia https://de.wikipedia.org/wiki/Lichtwellenleiter#Kategorien_f%C3%BCr_Multimodefasern
The English wikipedia article is, sadly, not as detailed as the German, compare if you want https://en.wikipedia.org/wiki/Optical_fiber .
"75Km is not very far. So you have crack regenerating the signal as an electrical signal."
No, regeneration only happens at 100's or 1000's of km intervals, determined by the capabilities of your specific fibres, error correction capabilities of the coding scheme in use, etc.
Analogue amplification of the composite optical signal is a different story though - yes, that does happen every 70km or so.
75Km is not very far.
Hate to break it to you, but undersea cables currently have repeaters/amplifiers every 70-150km on them already. It's not a single unrepeatered/unamplified run of 5000km (or whatever the actual distance is, I don't have a ruler that long) across the Atlantic.
75km puts it within the range of current, unamplified distances (at the lower end sure, but still within the range).
There's more to computer networking than the final mile, you know. Something has to connect head-ends/exchanges together. Something has to carry signals between ISPs. Something has to carry data between countries. Those somethings have to be high capacity because they carry the data being consumed by end-users such as yourself.
If every residential property in the UK had 50Mb/s (which on average it probably does) that's over 140Tb/s. Now as it happens no-one gets or needs 1:1 contention so there's a lot of sharing of bandwidth going on. But still, cables such as these are going to be very useful over the next few years.
It's unlikely they will ever be used to connect to your property but they could end up being used deeper in the network.
So they sent test patterns obviously so they could check it for errors.
It would be nice to leave it in situ hooked into a normal router so it actually does useful work.
The headline speed is impressive but simply making it compatible with existing gear will bring it to market.
One wonders if long-term use causes enough heating to stress the comb and shift the frequency spreading. Although I guess with that kind of device it has to have rock solid thermal management - i.e. a massive heatsink, like a lump of silver, and a Peltier to bleed off the excess heat in a controlled way.
Looks like we know what to do with our $60 billion surplus from the loan. We can phase out our ageing IPoAC** network.
Those poor pigeons must be exhausted after the recent increase of usage since the lockdown.
** https://en.wikipedia.org/wiki/IP_over_Avian_Carriers