• rbinv 10 days ago
    • martonlanga 10 days ago


      > Micro-combs - optical frequency combs generated by integrated micro-cavity resonators – offer the full potential of their bulk counterparts, but in an integrated footprint. They have enabled breakthroughs in many fields including spectroscopy, microwave photonics, frequency synthesis, optical ranging, quantum sources, metrology and ultrahigh capacity data transmission. Here, by using a powerful class of micro-comb called soliton crystals, we achieve ultra-high data transmission over 75 km of standard optical fibre using a single integrated chip source. We demonstrate a line rate of 44.2 Terabits s−1 using the telecommunications C-band at 1550 nm with a spectral efficiency of 10.4 bits s−1 Hz−1 . Soliton crystals exhibit robust and stable generation and operation as well as a high intrinsic efficiency that, together with an extremely low soliton micro-comb spacing of 48.9 GHz enable the use of a very high coherent data modulation format (64 QAM - quadrature amplitude modulated). This work demonstrates the capability of optical micro-combs to perform in demanding and practical optical communications networks.

    • dasudasu 9 days ago

      It is not particularly hard to do a "hero" experiment like this. Shannon limits to fiber transmission have pretty much been reached experimentally a long time ago. Muxing several wavelengths together is also of course the backbone of fiber optics transmission since its very origin. The current buzz in the field is to use micro-combs like they did as opposed to an array of lasers to provide the multiple wavelengths - but it still comes with its particular set of challenges to make it practical. The micro-comb provides the other wavelengths from a single source through a nonlinear process.

      My understanding from just looking quickly at the paper is that they don't modulate all the wavelengths independently, meaning that they duplicate the info they send several times to reach that high terabit rate. The laser source is only one part of a transceiver, and once you have 400+ independent modulators/receivers, the laser source becomes a much smaller concern when it comes to make it practical. A conventional laser source can be made very compact too (in a semiconductor platform) and integrated with the rest of the transceiver on the same chip. This is still where the industry is putting its efforts. These micro-combs come with some disadvantages too, relating to stability, low SNR, and uneven power among the wavelengths (that then need to be equalized).

      • cycomanic 9 days ago

        I agree with you that microcombs come with their specific kind of challenges (and SNR is the big one), however making many semiconductor lasers so small as too fit 100 on a single chip poses lots of challenges (in particular thermal management and wavelength stability). That said, combs (not necessarily microcombs) over opportunities for additional functionality/optimizations. Because the comb lines are locked to each other (normally individual lasers have small wavelength fluctuations) let's you space channels even closer together, as well as process multiple channels at the same time.

        Regarding your comment about these hero experiments not being hard, I would argue it's actually the other way around, we are now so close to the limits that it is becoming incredibly hard to observe further gains. Also regarding not modulating lines independently, this is the common way how everyone (even the industry labs) demonstrates these systems, using 100 independent transceivers would be prohibitevely expensive, moreover research has shown that you actually receive a penalty from using this approach so the demonstration is a lower bound on what could be achieved with individual tx modules.

        • dasudasu 9 days ago

          Modulating individual lines is the only way for such a scheme to become practical in a real environment and achieve the claimed data rates. Making hundreds of modulators and receivers fit within a single chip is about as hard as making hundreds of laser fit a single chip, hence why it's not realistically being pursued by the industry. My point is that if you already require separate chips for the rest of the transceiver, integrating the laser itself becomes much less of an issue, and the benefits of a single laser source common to all much more muted.

      • PopeDotNinja 10 days ago

        And even it that speed, I bet pre-roll ads on videos still end up buffering.

        • 6510 9 days ago

          Yes, we will find ways to spoil the gains arguing it doesn't matter.

          • Denvercoder9 9 days ago

            Yes, we need better software (engineers).

            • tudorw 9 days ago

              And we need better consumers, kidding, we love you.

          • vaer-k 9 days ago

            According to https://hpbn.co/primer-on-latency-and-bandwidth/#bandwidth-i...

            > As of early 2010, researchers have been able to multiplex over 400 wavelengths with the peak capacity of 171 Gbit/s per channel, which translates to over 70 Tbit/s of total bandwidth for a single fiber link!

            So why/how is 44 Tbps an improvement?

            • vaer-k 9 days ago

              Ah ok, so according to the article (https://www.nature.com/articles/s41467-020-16265-x.pdf),

              > To dramatically increase bandwidthcapacity, ultrahigh capacity transmission links employ massivelyparallel wavelength division multiplexing


              > All of this is driving the need forincreasingly compact, low-cost and energy-efficient solutions


              > The ability to supply all wavelengths with a single, compact integrated chip,replacing many parallel lasers, will offer the greatest benefits

              So it's not really so much news in the sense that existing speeds over fiber have been improved, but instead in the sense that the speed produced by this single chip is a viable compact, low-cost and energy-efficient alternative to many parallel chips

              • detaro 9 days ago

                The improvement here seems to be "single chip" source.

              • ganzuul 9 days ago

                I have this funny idea about a waveguide interconnect, where MIMO radios address each other inside the manifold. You could get pretty decent bus width through e.g QAM and with beam steering probably simultaneous data links.

                Of course it could be made to look cool as hell, complex microwave plumbing with integrated heatsink replacing a plain old mainboard. :)

                • cycomanic 9 days ago

                  This has actually been a big research topic over the last 8 years or so. The keywords are space division multiplexing (SDM) and in particular Mode division multiplexing (MDM)

                • bobajeff 10 days ago

                  I like like the bottle neck in the future will be Harddrive/SSD file read/write speeds.

                  Honestly, I'd love to have my hands on a terabyte drive with 1TBps speeds.

                  • rayiner 9 days ago

                    It’s not even the future. 40 gig Ethernet is already faster than most SSDs. And you can get a card on eBay for $200.

                    • dahfizz 9 days ago

                      I think latency of a network will always lag behind that of local storage.

                      Even traveling at the speed of light, going around the circumference of the earth takes over 100ms. Obviously not all network requests go around the globe, but the fact that local storage is physically closer to your computer will always be a sizeable advantage.

                      • hutzlibu 9 days ago

                        Plus the fact that cloud storage has to be stored on physical storage as well ...

                      • zepearl 9 days ago

                        I'm sending right now at home 7TB from my server to my NAS and it's taking aaages over my internal 1Gb/s ethernet network.

                        Am I right thinking that there are (still) no SOHO network switches that can handle faster speeds (at least 2Gb/s) that don't have active fans & don't get hot and that aren't super-expensive? The last time I checked, about 1 year ago, I didn't manage to find anything.

                        • jlgaddis 9 days ago

                          I've not used one and can't speak to their quality but:

                          > The CRS305 is a compact yet very powerful switch, featuring four SFP+ ports, for up to 10 Gbit per port. The device has a 1 Gbit copper ethernet port for management access and two DC jacks for power redundancy. The device is a very sleek and compact metallic case without any fans, for silent operation. [0]

                          > Suggested price $149.00


                          [0]: https://mikrotik.com/product/crs305_1g_4s_in

                          • zepearl 9 days ago

                            Thank you - looks interesting, but they don't write in the specs if it has an active fan or not, right? (e.g. I see in the pics that this random model has fans https://mikrotik.com/product/crs328_4c_20s_4s_rm#fndtn-downl... but they're not mentioned in the specs)

                            • jlgaddis 9 days ago

                              I didn't look through the specs in detail so I'm not sure, but according to the copy I quoted above:

                              > ... without any fans ...

                          • unholythree 9 days ago

                            You could always just put a fast NIC in those two machines and just go point to point no switch involved.

                            • zepearl 9 days ago

                              Yeah, your right => I did take this into consideration in the past and now you woke up once more those thoughts.

                              Still not optimal, as I have another PC/server involved which needs from time to time as well a lot of data (but more rarely).

                            • wtallis 9 days ago

                              Anything with multi-Gig or 10GbE is still quite expensive, unless you score a good deal on used enterprise gear that will definitely have screaming fans. There are a few switches that have mostly 1GbE ports and a few 10G ports and are fanless.

                              • Define expensive? 10GbaseT is not that much anymore. Also a number of vendors are supporting 2.5/5G speeds. Ubiquity has some reasonable kit. I am planning on dropping a 10G into my FreeNAS box and getting a thunderbolt 10G for my MacBook. The idea that the 10GT PHY can work in an adapter is pretty cool. Back in the day I worked at a startup that did one of the first 48x10GT switches and the PHY was 5 watts each x 48. Sorting the cooling was fun. As DC switch the noise was fine, but working with the prototypes at your desk or in the lab was quite loud.

                                • wtallis 9 days ago

                                  For switches of around 8 ports, 1GbE is about $2-3 per port. 10GbE over copper is about $70 per port, way higher than justified by the bandwidth increase alone. 10GbE is getting cheaper, sure, but it definitely isn't cheap yet. A 10GbE switch is still more expensive than all the equipment required for a 1GbE+WiFi home network.

                                  • zepearl 9 days ago

                                    I just did some research: this switch doesn't seem bad, or am I overlooking something?


                                    Fanless, 24 normal ports, 4 10GbE ports.

                                    What do they mean when they write "...with 4 10Gb SFP+ Uplinks"? Are they meant only to aggregate the traffic that comes from the 1GbE-ports or can they be used as well to exchange traffic between 4 servers, each one using 10GbE?

                                    • wtallis 9 days ago

                                      That switch should be able to do regular switching between its four 10Gb ports, but first you need to buy SFP+ transceivers to plug into those ports. 10G Fiber transceivers start around $20 per port, but 10G transceivers with RJ-45 ports for ordinary twisted-pair copper cabling are $40-70 per port. So to get that switch equipped to actually do 10Gb switching over copper would drive the price per port over $100.

                          • dasudasu 9 days ago

                            Electro-optic conversion is expensive in terms of power, so you better be sure it's necessary. There are still some people looking at hybrid computers with both optics and electronics. To be practical, you'd need both to be realized in the same platform, but they don't exactly work on the same scales, and laser integration is a big issue.

                            • IdiocyInAction 9 days ago

                              Memory access latency is already the biggest bottleneck when it comes to optimization, both disk and RAM.

                              • coribuci 9 days ago

                                > I like like the bottle neck in the future will be Harddrive/SSD file read/write speeds.

                                No. It will be your ISP

                                > Honestly, I'd love to have my hands on a terabyte drive with 1TBps speeds.

                                You need also a fast processor and RAM to to take advantage of it.

                              • The_rationalist 10 days ago
                                • oarsinsync 9 days ago

                                  That was over 1km utilising 7 cores. Typical fibre plants use one core per direction (transmit / receive).

                                  This is over 75km utilising a single core per direction. IE this is actually something that has potential to be deployed in the world without having to replace all the existing fibre plants that already exist (eg undersea cables)

                                  • souterrain 9 days ago

                                    It would be interesting to see if EDFAs also do not require retrofit.

                                • mcnamaratw 9 days ago

                                  The article seems to be comparing a hero experiment to access rates. Why not at least compare to telecom backbone rates? You can do at least 1.6 Tbps per fiber, long haul, with commercially available gear.

                                  If we use telecom hero experiments as the standard, 44 Tbps is not the record: https://en.wikipedia.org/wiki/Fiber-optic_communication#Stan...

                                  • rayiner 9 days ago

                                    It’s not “internet speed” if you can’t route at that speed.

                                    • wbl 9 days ago

                                      Bundled links via ECMP or even round robin are a valid strategy.

                                      • A single flow hashs to a single link, so a file transfer is at the speed of a single link in a ECMP group if ECMP method is normal Ethernet switching.

                                    • lostlogin 9 days ago

                                      > The highest commercial internet speed anywhere in the world is currently in Singapore, where the average download speed is 197.3 megabits per second (mbps).

                                      I’m very surprised by this. I would have assumed the leading country would have had something a lot closer to gigabit. ‘Good enough’ must be the user reaction. Years of terrible connections have left me chasing down every last bit, even though fibre is now installed.

                                      • ksec 9 days ago

                                        Because that assumption would means everyone is getting a GPON / Fibre Network. In reality even if 20% of the nation is still connected via ADSL, your average speed would have been significantly lowered.

                                        I still think we haven't fully solved the last mile problem yet. Fibre installation still sucks for most people. And vast majority of new home dont have additional pipes for Fibre built in.

                                        • LeoPanthera 9 days ago

                                          I wonder if that figure includes WISPs and cellular, which would bring down the average considerably.

                                        • keenmaster 9 days ago

                                          Is anyone knowledgable on the implications of the underlying tech once it gets commercialized? Obviously things like game streaming would be improved.

                                          • stephen_g 9 days ago

                                            This isn't the kind of thing that we're going to see in home internet for a long time. The newest WiFi standard is only 10Gbps at best, and routers and wired standards aren't affordable over 10Gbps yet either for home use. For internet connections, there are currently already consumer standards that can do 10Gbps symmetric (like NG-PON2) which hopefully we see being deployed more widely soon. Even in 15 years I would be surprised if the high-end of available speeds for home connections are more than 2-5x that (Of course, companies that can pay for dedicated links can already get 100Gbps+ today).

                                            The technology in the article, if commercially practical, would first go in to carrier networks and the larger enterprise market for backhaul transit links in the next few years, then over time filter down to general enterprise networking.

                                            Even if transit providers upgrade, it wouldn't actually be a noticeable change, because they can already do this kind of link, just with a rack with dozens of laser modules that are optically multiplexed together. This does that in a single chip which would reduce cost a lot.

                                            • throwawaygh 9 days ago

                                              We will be able to make comments complaining about bloated JavaScript libraries at lightning speed.

                                              • thejynxed 9 days ago

                                                You aren't kidding, the bloated JavaScript libraries will make my browsing session feel like a blistering 55.6k bps instead of the piddly 11.4k bps they do now.

                                                • 6510 9 days ago

                                                  For a while at least.

                                              • dahfizz 9 days ago

                                                This improves the speed achieved with a single chip, not the actual maximum speed possible with fiber. We already have links that can go faster than this, this invention will likely just make those high speed links cheaper / more compact / easier to manufacture.

                                                • cycomanic 9 days ago

                                                  The research here is all about core and metro networks, so those are the networks connecting metropolitan areas to each other and the ones connecting the big users within metro areas. The home users and mobile users are not directly connected to these networks, but through e.g. your providers passive optical network. You can think about this similar to a road network, you are living on the little side roads, these are the big highways and ring roads. But because everyone is using more and more data on their home and mobile devices, there needs to be bigger pipes in the core network (despite more and more local data centres for caching)

                                                  • dasudasu 9 days ago

                                                    This would never be for a home access point. This would be used for long-haul communications (i.e. between metro areas). The data rates there are already pretty ludicrous. The current standard is called 800G, for 800 Gbit/s per wavelength.

                                                    • TheSpiceIsLife 9 days ago

                                                      Aren’t gamers primarily concerned with latency rather than speed?

                                                      • TheAdamAndChe 9 days ago

                                                        They said game streaming, which makes me think s/he's talking about things like Twitch and Mixer, livestreaming platforms that do depend on throughput for high quality video.

                                                      • govg 9 days ago

                                                        Both latency and bandwidth affect gaming. Latency is important to ensure that there isn't too much lag between you moving a controller stick and your character moving, and not as important for slower games which can handle this well. Bandwidth is important because it determines the resolution and quality you can stream at, so higher bandwidths would enable full HD or 4K gaming.

                                                        • thejynxed 9 days ago

                                                          Well, if you use things like nVidia Shield for remote streaming you want both.

                                                      • kraussvonespy 7 days ago

                                                        Even this wouldn't be enough bandwidth for my clueless wifi users who complain when speedtests on their smartphone show 70mbps.

                                                        "Is there enough bandwidth to do what you need to do? Yes? Then shut up."

                                                        • billme 9 days ago

                                                          Given the cost of laying fiber lines across the ocean and this tech (appears) to double the capacity of an existing line, why would there not be a push to get this into use, what am I missing?

                                                          • detaro 9 days ago

                                                            This is a field that's constantly being worked on, not sure why you say there isn't a "push" in it.

                                                            This specific thing is not faster than previous results, but more compact.

                                                            Long-distance fiber lines also have amplifiers along the way, so you can't just scale them up by changing the endpoints if it doesn't match the capability of the in-line hardware.

                                                            • cycomanic 9 days ago

                                                              That is incorrect the amplifiers have the capacity to amplify lots of channels simultaneously. So it is sufficient to only upgrade the endpoints (unless your fibre is full, where full means the bandwidth of the amplifiers, ~100 Tb/s for a single fibre). This has in fact been the driver behind the tremendous growth in data rates we have seen in the last 30 years. Operators can incrementally upgrade links by upgrading the endpoints. To transfer a MB across the network was 100s of $ in the 90s and is now essentially free (it's like 10e-4 cents or sol

                                                              • billme 9 days ago

                                                                Cost of swapping the amplifiers, not just the end-points, makes sense as an issue. Thanks!

                                                                As for it being “only more compact” not a capacity increase, for a comparable single coherent optical fiber line, are existing fibers filled to capacity due to the limits of tech, economies, physics, etc. - if physics, then I assume all fibers are at capacity, right?

                                                                • dasudasu 9 days ago

                                                                  If you're going to lay a fiber across the oceans, then yeah, that capacity is going to approach the Shannon limit, but at some point there is a calculation to be made about how expensive it is to use all that capacity vs using multi-core fibers or just laying out more fibers.

                                                                  The economics of it are pretty interesting. A single fiber (non-submarine) is about ¢8 a meter in raw cost, and it said that they laid out so many during the telecom bubble of the late 1990s that there are still many unused (so-called dark) fiber networks throughout the US. See for example https://www.ofsoptics.com/lighting-up-dark-fiber/

                                                                • eternauta3k 9 days ago

                                                                  When do you have to replace an EDFA?

                                                              • acd 9 days ago

                                                                Looking forward to a 1 terabit/second home Internet connection.

                                                                • andarleen 9 days ago

                                                                  One can barely get 1Gbps connections in the UK, and in most parts even 10Mbps is a lot. TBps may have to wait a few eons.

                                                                • fnord77 10 days ago

                                                                  > The highest commercial internet speed anywhere in the world is currently in Singapore, where the average download speed is 197.3 megabits per second (mbps).


                                                                  • saberience 9 days ago

                                                                    Err dude, you aren't reading. This is AVERAGE speed. The average internet speed in the US or UK is nowhere near 197 megabits. In the UK it's 28.9Mb and in the US 32Mb.

                                                                    • fnord77 6 days ago

                                                                      > The highest commercial internet speed anywhere in the world is currently in Singapore

                                                                      This does not say "average". They don't use "average" until the 2nd half of the sentence. If that's what they meant, then they didn't communicate this clearly. For instance, this would not fly in a legal context.

                                                                    • notaplumber 10 days ago

                                                                      Yeah, this confuses me. Gigabit is available in several places in North America. I had to check the date on the article.. posted 20 hours ago. Yep. Still confused.

                                                                      • > where the average download speed is 197.3 megabits per second (mbps).

                                                                        Average is the key word there. Higher speeds may be available but just not used by many people die to cost.

                                                                        In New Zealand for example 95% of the population has access to gigabit (with 10 gigabit being tested in places) speeds but the average download speed is only around 50 mbps due to most people opting for slower/cheaper plans.

                                                                        • 6510 9 days ago

                                                                          My ISP in the Netherlands made slow plans only a few euro cheaper than fast ones. 50 mbit = 46.50, 250 mbit = 56.50, 500 mbit = 64.50, 1000 mbit = 76.50

                                                                        • shric 9 days ago

                                                                          Yes, but this is average across the country. Singapore has a rather unfair advantage of being a city state.

                                                                          • Spooky23 9 days ago

                                                                            It’s still better than any metro area in the US.

                                                                            The average speed in NYC is 18.2 mbps.

                                                                          • z3t4 9 days ago

                                                                            In Sweden we have 10Gbe consumer Internet for $40/month

                                                                            • myko 9 days ago

                                                                              I'm paying $50/mo for 1Gb in the US. I thought I was doing well

                                                                              • jraph 9 days ago

                                                                                I am paying 13€/mo for 600M down, 60M up, unlimited (France). The plan is actually 1Gb but this cannot be reached in my flat.

                                                                                But the Internet is slow and/or unreliable in many places in the country side, when available at all. We are far from having these speed on average across the country.

                                                                              • snovv_crash 9 days ago

                                                                                ... and then put a wifi router in front of it, am I right?

                                                                                • thejynxed 9 days ago

                                                                                  To be fair, here we have some counties as large as Sweden with fewer people living in them.

                                                                                  • sollewitt 9 days ago

                                                                                    Sweden is the size of California.

                                                                                    • jsjohnst 9 days ago

                                                                                      True. It also has one quarter the population too.

                                                                                • elorant 9 days ago

                                                                                  Average speed, not the top available. Singapore has 5,6m citizens and 75% of them have an Internet connection. So an average speed of 197Mbps is pretty impressive.

                                                                                  • im3w1l 9 days ago

                                                                                    When you ask about top of the averages, it becomes critically important at what scale you average and how you gerrymander. Given that Singapore is both a city and a country comparing it to either seems fair.

                                                                              • tl;dr: "chips with friggin laser beams attached to their head"

                                                                                • amelius 10 days ago

                                                                                  This is not directly internet related. The original title is better:

                                                                                  > Ultra-dense optical data transmission over standard fibre with a single chip source

                                                                                  As a compromise, I'd propose:

                                                                                  > 44.2 terabit/s optical data transmission over standard fibre with a single chip source

                                                                                  • YayamiOmate 9 days ago

                                                                                    Much better, because what the heck is "internet speed". The most sensible definition to me is payload over IP protocol possibly on an existing commercial link. That's the only way I see relation to internet and the internet.

                                                                                    • jlgaddis 9 days ago

                                                                                      In the past, the "Internet speed record" was measured in units such as "terabit meters-per-second":

                                                                                      > ... they had managed to send nearly 840 gigabytes of data across a distance of 16,346 kilometers (10,157 miles) in less than 27 minutes, at an average speed of 4.23 gigabits per second.

                                                                                      > This was equal to 69,073 terabit meters per second (or 69,073 trillion bits sent through one meter in a second), which exceeded the previous record set by CalTech and CERN earlier this year. [0]


                                                                                      > The team successfully transferred data at a rate of 8.80Gbps, which is equal to 264,147 terabit-meters per second (Tb-m/s). [1]


                                                                                      > Internet2 ... has this week announced a stunning new record speed of 9.08Gbps - equal to 272,400 terabit-meters per second (Tb-m/s) [2]


                                                                                      No idea if it's still done that way or not but I don't see any mention of distance in this article (haven't looked at the paper).


                                                                                      [0]: https://www.cnet.com/news/internet-speed-record-broken/

                                                                                      [1]: http://www.startap.net/translight/pages/applications/2006/da...

                                                                                      [2]: https://www.hindustantimes.com/india/the-speed-fantasy/story...

                                                                                      • rejberg 9 days ago

                                                                                        > In the past, the "Internet speed record" was measured in units such as "terabit meters-per-second":

                                                                                        I like this unit better, because then a jetliner full of hard drives could be a valid competitor.

                                                                                        • ChuckMcM 9 days ago

                                                                                          Which is exactly why it was chosen, the 'purpose' of networks is moving data from point A to point B so the 'goodness' of networks is how much data from point A to point B and how far away is point A from point B.

                                                                                          Then the Internet became a transport for time sensitive data (movies, voice, Etc.) and so the latency between bits gets wedged in sometimes.

                                                                                      • monocasa 9 days ago

                                                                                        IDK, I get it. WAN backbone rates over a single fiber rather than more typical LAN rates.

                                                                                      • MR4D 9 days ago

                                                                                        But it is directly internet related. If you check the actual paper [0] - I had to search for it - you will see this quote:

                                                                                          We demonstrate transmission over 75 km of fibre in the
                                                                                          laboratory as well as in a field trial over an installed
                                                                                          network in the greater metropolitan area of Melbourne,
                                                                                        Technically that 75 km was between two different labs running on dark fiber. They state more detail in this quote:

                                                                                          These cables were routed from the labs access panels, 
                                                                                          to an interconnection point with the AARNet’s fibre
                                                                                        [0] - https://www.nature.com/articles/s41467-020-16265-x
                                                                                        • dang 9 days ago

                                                                                          I've taken a crack at it.

                                                                                        • kneel 9 days ago

                                                                                          The human penis still reigns supreme at 13500 terabits/sec