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> The critically important cable that connects Svalbard to the mainland is no thicker than a pinkie finger This is amazing. I wonder how much data per unit of

> The critically important cable that connects Svalbard to the mainland is no thicker than a pinkie finger This is amazing. I wonder how much data per unit of time this is capable of transporting. Wikipedia says "Each segment has a speed of 10 gigabits per second (Gb/s), with a future potential capacity of 2,500 Gbit/s." [1] Wikipedia also notes that NASA helped fund this system. [1] https://en.wikipedia.org/wiki/Svalbard_Undersea_Cable_System https://en.wikipedia.org/wiki/Svalbard_Undersea_Cable_System

Scoundreller 2y ago
I think NASA helped fund it because they wanted more (And more reliable) data to a groundstation on the island, not because this subsea cable is anything special. Fibre optic is great because you can usually add more bandwidth by lighting up another wavelength. The amplifiers don't need to be substituted if the wavelength is within its range.
- _zoltan_ 2y ago
  I've wondered in the past: is there an actual theoretical upper limit based on the physicality of it on the bandwidth of a single fibre link?
  - dboreham 2y ago
    Shannon bound. But it's very large. I don't think we're anywhere close with current DWDM emitter/detector technology.
    - candiddevmike 2y ago
      OS2 single mode fibre is pretty future proof. The transceivers may change, but the underlying cable should last a looong time and can be sliced and diced considerably with WDM (16+ channels AFAIK).
    - cycomanic 2y ago
      Actually we know that a single mode fibre (there would typically quite a lot of them in a cable) can carry around 100 Tb/s in the C band (used by most systems due to amplifier availability) over about 100km. Research systems have reached that limit and commercial systems are not very far off.
      - oh_my_goodness 2y ago
        Is that right? The C band is only 4 or 5 THz wide, so that's impressive packing. (I'm way out of date, I know there is QAM and whatever.)
        pezezin 2y ago
        Modern DWDM systems use a channel spacing of 75/100 GHz, so you easily fit more than 50 channel in a single fibre.
        deleted 2y ago
        [deleted]
        cycomanic 2y ago
        For the super high capacity demonstrations, 256 QAM and/or probabalistic/geometric shaping is typically used so we get to about 12 bit/s/Hz (accounting for FEC and pilot overheads). Interestingly, data rates are mainly limited by the transceivers (RF amplifiers, DAC/ADC ENOB... is not that great at 25-100GHz, which is required for the 50+Gbaud symbol rates).
Hikikomori 2y ago
Locals liked to say they had the best internet connection in the worlds, idk about that. NASA is a customer of the satellite station there.
varenc 2y ago
> I wonder how much data per unit of time this is capable of transporting. The max throughput of fiber optic cables isn't exactly constant. As fiber optic modem and DSP technology improves you can get much higher speeds on 15+ year-old cables than were ever possible when they were laid. Recently I saw an article about researchers getting 300,000 Gbit/s over existing fiber optic cables (though I'm sure that's a long way from being a deployable technology): https://www.aston.ac.uk/latest-news/aston-university-researchers-send-data-45-million-times-faster-average-broadband https://www.aston.ac.uk/latest-news/aston-university-researc...
- SAI_Peregrinus 2y ago
  This applies to single-mode cables, but much less to multi-mode cables. Of course long-distance cable like this is always single-mode, but it's worth keeping in mind if building a fiber network inside a building.
  - a20eac1d 2y ago
    Can you use single mode fiber in a house, or do the transceiver only work over much longer distances? Is transceiver burn out an issue?
    - jtriangle 2y ago
      You can use SM for short runs, you just have to match the optics to the cable/distance you're looking to use. Tons of very fast single mode optics out there that only expect <300m runs. That said, it's likely not worth it, given that cabling is typically viewed as a ~10 year investment, and if you're installing OM4 Multimode fiber in a house you're not likely to hit the limit of that fiber within 10 years even in extreme use cases.
      - a20eac1d 2y ago
        But why stop at 10 years? If the theoretical bandwidth limit of SM Fiber is above 100 Gbit/s then there is simply no way that a household will need more internal bandwidth than that. Even for the next 20-30 years, because other technologies (like SATA) will be the limiting factor. I believe this could be a case of future proofing that will actually last 30-40 years, no?
mvkel 2y ago
Wait, an entire mainline for a country can do 10Gb/s and people somehow are paying for gigabit home Ethernet? Either the former is understated, or the latter is way overkill. Or, I'm misunderstanding. Which is probably the most likely possibility.
- EKS1 2y ago
  svalbard is a island, far away from mainland. Not many live there (3k people). But they likely have higher seasonal numbers (Tourists) https://www.openstreetmap.org/#map=5/77.504/13.008 https://www.openstreetmap.org/#map=5/77.504/13.008
- saithound 2y ago
  Svalbard is not a country, but a remote archipelago of Norway. The main island, Spitsbergen has a population of 2.5k people, they don't allvuse the Internet (certainly not all at the same time), and they do not pay for gigabit home internet, more like 75Mbps. For reference, the Southern Cross fiber network connecting Australia to the U.S. does more like 10+ Tbps.
  - ocdtrekkie 2y ago
    All of this but also even in the case of bigger lines, a lot of home Internet traffic is not routed globally if you can avoid it. CDNs cache content on the same physical continent as much as possible, things like Netflix are usually streamed from your local ISP. A lot of traffic over the Internet is extremely unexciting things like Windows updates as well, which are generally globally served by a CDN (or even peer to peer sharing from other Internet users nearby).
    - guappa 2y ago
      Before https anyone could put a proxy and cache content.
- svnt 2y ago
  Each individual fiber, which is a fraction of a cubic mm in cross sectional area, can provide this much bandwidth in a fairly trivial low-cost configuration. Cables like the one pictured carry many of these fibers.

Scoundreller 2y ago

I think NASA helped fund it because they wanted more (And more reliable) data to a groundstation on the island, not because this subsea cable is anything special. Fibre optic is great because you can usually add more bandwidth by lighting up another wavelength. The amplifiers don't need to be substituted if the wavelength is within its range.

_zoltan_ 2y ago
I've wondered in the past: is there an actual theoretical upper limit based on the physicality of it on the bandwidth of a single fibre link?
- dboreham 2y ago
  Shannon bound. But it's very large. I don't think we're anywhere close with current DWDM emitter/detector technology.
  - candiddevmike 2y ago
    OS2 single mode fibre is pretty future proof. The transceivers may change, but the underlying cable should last a looong time and can be sliced and diced considerably with WDM (16+ channels AFAIK).
  - cycomanic 2y ago
    Actually we know that a single mode fibre (there would typically quite a lot of them in a cable) can carry around 100 Tb/s in the C band (used by most systems due to amplifier availability) over about 100km. Research systems have reached that limit and commercial systems are not very far off.
    - oh_my_goodness 2y ago
      Is that right? The C band is only 4 or 5 THz wide, so that's impressive packing. (I'm way out of date, I know there is QAM and whatever.)
      - pezezin 2y ago
        Modern DWDM systems use a channel spacing of 75/100 GHz, so you easily fit more than 50 channel in a single fibre.
        deleted 2y ago
        [deleted]
      - cycomanic 2y ago
        For the super high capacity demonstrations, 256 QAM and/or probabalistic/geometric shaping is typically used so we get to about 12 bit/s/Hz (accounting for FEC and pilot overheads). Interestingly, data rates are mainly limited by the transceivers (RF amplifiers, DAC/ADC ENOB... is not that great at 25-100GHz, which is required for the 50+Gbaud symbol rates).

Hikikomori 2y ago

Locals liked to say they had the best internet connection in the worlds, idk about that. NASA is a customer of the satellite station there.

varenc 2y ago

> I wonder how much data per unit of time this is capable of transporting. The max throughput of fiber optic cables isn't exactly constant. As fiber optic modem and DSP technology improves you can get much higher speeds on 15+ year-old cables than were ever possible when they were laid. Recently I saw an article about researchers getting 300,000 Gbit/s over existing fiber optic cables (though I'm sure that's a long way from being a deployable technology): https://www.aston.ac.uk/latest-news/aston-university-researchers-send-data-45-million-times-faster-average-broadband https://www.aston.ac.uk/latest-news/aston-university-researc...

SAI_Peregrinus 2y ago
This applies to single-mode cables, but much less to multi-mode cables. Of course long-distance cable like this is always single-mode, but it's worth keeping in mind if building a fiber network inside a building.
- a20eac1d 2y ago
  Can you use single mode fiber in a house, or do the transceiver only work over much longer distances? Is transceiver burn out an issue?
  - jtriangle 2y ago
    You can use SM for short runs, you just have to match the optics to the cable/distance you're looking to use. Tons of very fast single mode optics out there that only expect <300m runs. That said, it's likely not worth it, given that cabling is typically viewed as a ~10 year investment, and if you're installing OM4 Multimode fiber in a house you're not likely to hit the limit of that fiber within 10 years even in extreme use cases.
    - a20eac1d 2y ago
      But why stop at 10 years? If the theoretical bandwidth limit of SM Fiber is above 100 Gbit/s then there is simply no way that a household will need more internal bandwidth than that. Even for the next 20-30 years, because other technologies (like SATA) will be the limiting factor. I believe this could be a case of future proofing that will actually last 30-40 years, no?

mvkel 2y ago

Wait, an entire mainline for a country can do 10Gb/s and people somehow are paying for gigabit home Ethernet? Either the former is understated, or the latter is way overkill. Or, I'm misunderstanding. Which is probably the most likely possibility.

EKS1 2y ago
svalbard is a island, far away from mainland. Not many live there (3k people). But they likely have higher seasonal numbers (Tourists) https://www.openstreetmap.org/#map=5/77.504/13.008 https://www.openstreetmap.org/#map=5/77.504/13.008
saithound 2y ago
Svalbard is not a country, but a remote archipelago of Norway. The main island, Spitsbergen has a population of 2.5k people, they don't allvuse the Internet (certainly not all at the same time), and they do not pay for gigabit home internet, more like 75Mbps. For reference, the Southern Cross fiber network connecting Australia to the U.S. does more like 10+ Tbps.
- ocdtrekkie 2y ago
  All of this but also even in the case of bigger lines, a lot of home Internet traffic is not routed globally if you can avoid it. CDNs cache content on the same physical continent as much as possible, things like Netflix are usually streamed from your local ISP. A lot of traffic over the Internet is extremely unexciting things like Windows updates as well, which are generally globally served by a CDN (or even peer to peer sharing from other Internet users nearby).
  - guappa 2y ago
    Before https anyone could put a proxy and cache content.
svnt 2y ago
Each individual fiber, which is a fraction of a cubic mm in cross sectional area, can provide this much bandwidth in a fairly trivial low-cost configuration. Cables like the one pictured carry many of these fibers.