7 ms·

None of these technologies allow you to exceed the available bandwidth. They just make use of the shared bandwidth more efficient. It's still a shared medium.

by yarcob 6y ago

None of these technologies allow you to exceed the available bandwidth. They just make use of the shared bandwidth more efficient. It's still a shared medium. Where I live, a lot of people have 3G internet because mobile data is pretty cheap and the companies advertise it as an alternative to cable. And now they all have really crappy internet. In the evening when everyone watches youtube you get a fraction of the advertised bandwidth. With fibre, every customer gets the full spectrum. And since the frequency of light is a lot higher than radio frequency, you also get a lot more bandwidth. At radio frequency we're already hitting the physical bandwidth limits; with optical transmission there's still a lot of bandwidth left. Thinking that radio frequency transmissions are an alternative to cable / fibre is pretty short sighted thinking. Data usage is going to grow, more devices are going to use data, and wireless transmission is going to seriously limit us.

michaelmrose 6y ago
You are dead on. We are still transitioning from HD to 4k with 8k coming eventually. The difference in HD to 8k is 17x the bandwidth.
- ksec 6y ago
  >The difference in HD to 8k is 17x the bandwidth. The pixel is 17x, not bandwidth. Even Compressed RAW size dont scale linearly with pixel count. I dont have any experience with 8K, but compressing / encoding 4K with HEVC or AV1 tends to easier with fixed VMAF score than a comparatively low pixel count of 2K / 1080P. I would imagine the same if not better for 8K. And that is discounting the use of much better video codec like VVC which brings another 40 to 50% reduction in bitrate.
  - michaelmrose 6y ago
    Good point.
- AlexandrB 6y ago
  Unless you're displaying on movie theatre sized screens, 8K seems like a waste of space/bandwidth. Even 4K is generally overkill for the typical living room. I think we're hitting the point with video resolution that music CDs hit with audio, where improvements in fidelity are largely outside the range of human perception. It's one of the reasons the music DVDs and SACDs never really caught on.
  - elzbardico 6y ago
    Not sure about that. With large screens 55" at home and over I can see a difference between FHD and 4K, enough to know I am having network problems when the streaming service starts to downscale the resolution in a 4k video.
    - leetcrew 6y ago
      that could be the bitrate more than the resolution. streams are highly compressed. would be interesting to see whether you prefer 1080p bluray over a 4k netflix stream (I suspect yes).
  - michaelmrose 6y ago
    1080p at 65 34ppi 4k at 65" 65ppi 8k at 65 135ppi This is well within what someone with good vision can see at for example 6-8 feet For a personal reference I could tell the difference in clarity at 8 ft between a 1080p 24" monitor and a 28"4k monitor. That is 157 vs 92 ppi on a screen a fraction of the size 5 minutes ago. I must imagine people making such claims have poor eyesight or are using optimum viewing charts as a proxy for distances wherein human vision was sufficiently acute instead of looking for themselves. For reference someone with good vision ought to be able to distinguish up to about 115ppi at 8ft according to this source. https://www.quora.com/What-is-the-highest-resolution-humans-can-distinguish https://www.quora.com/What-is-the-highest-resolution-humans-... The source seems valid despite the mixed bag that is quora. Especially since I and many others can verify this in 10 seconds. Edit: I wrote 43 instead of 34 by accident. 65" and 1080p = 34ppi
    - 6y ago
- Syonyk 6y ago
  > The difference in HD to 8k is 17x the bandwidth. Not practically. NetFlix will just compress it down to 3Mbit anyway like they do with 4k, but be able to call it "8k content!" and (probably) charge a premium for it.
- gumby 6y ago
  It remains to be determined. Quadrophonic sound did not replace the "good enough" stereo even though humans can move their heads. Of course an 8K TV is just as easy to set up as a 4K one, unlike a quadrophonic stereo. And the functionality of quadrophonic records became available as "surround sound" which some people do have. It's possible there are enough people who will appreciate the difference for 8K to become established. Personally I doubt it, but it's certainly possible. Another possibility is that your TV watches you and provides just a 4K or 4K-ish image unless you walk close to your TV at which point it displays a higher resolution image where you are looking. Possibly with some hint-driven mix of AI upsampling and more image data. The opposite could be true of course with 8K VR rigs in every home. I also doubt it, but it's quite possible. The 8K-production -> 4K result is well established and will remain even if my guesses above turn out to be correct. That needs a lot of bandwidth but not at the point of viewing.
mcny 6y ago
Level 3/CenturyLink/Lumen CEO reassured panicked investors and employees scared that their company would be worthless with 5G and beyond by basically saying that the last mile will increasingly become the last tens or hundreds of meters and that fiber is still the infrastructure on which these increasingly dense base stations depend on. And that the “edge computing” will likely live on the cabinets owned by the fiber provider. It makes sense to me. Just add more fiber and let people access them over whatever. My biggest gripe is we could choose to do away with licensing fees and spectrum auctions and open mm wave 5G to be something like Wi Fi but we are shortsighted as usual.
ksec 6y ago
>Where I live, a lot of people have 3G internet. Well, yes 3G is Shared Spectrum. >None of these technologies allow you to exceed the available bandwidth Exceed available bandwidth of what? Per Spectrum? Shannon–Hartley theorem? The whole point of 4G, and 5G, mentioned in the GP as Massive MIMO was that we could workaround those limits with more Antenna. Everything we are doing today and aiming to do in 3GPP Rel 17 in a few years time are literally impossible to even infer about in the early 2000s. When Massive MIMO, or it was known as Very large Array of Antenna was first published people called the idea "crazy". And CoMP, whether the marketing decide to call it 5.5G or 5.9G along with distributed antennas being worked on in 6G. There are no fundamental technical reason why we cant have a fully wireless Internet. Although there are many business and economical reason why this may never happen.
- yarcob 6y ago
  >>Where I live, a lot of people have 3G internet. >Well, yes 3G is Shared Spectrum. Sorry, I think I meant 4G, not 3G. It's marketed as LTE here. > Exceed available bandwidth of what? Per Spectrum? Shannon–Hartley theorem? No, not Shannon-Hartley. That's just a mathematical model. When EM waves propagate, they are subject to diffraction, which limits both the amount of information that can be transmitted per time interval, and also the spatial resolution of the transmission. Even with antenna arrays or distributed antennas you can't get past diffraction limits; you can just get closer to them. To get around diffraction limits, you need to use higher frequencies / shorter wavelengths. (Which has the side effect that you loose the ability of signals to go around / through obstacles, so you need a lot more cell towers.) We're at a point where new technologies just make different trade-offs (eg. shorter wavelengths for areas with lots of wireless clients vs. longer wavelengths for sparse areas). With a fibre connection, you don't need to make these tradeoffs; you just need to dig up the ground and you can have as much bandwidth between two points as you want.
vel0city 6y ago
A bit of a nitpick, but most residential fiber deployments are PONs. With a PON, a single fiber gets split into a lot of separate wavelength channels with prisms. It's still tons more usable bandwidth available than wireless. https://en.m.wikipedia.org/wiki/Passive_optical_network https://en.m.wikipedia.org/wiki/Passive_optical_network
gumby 6y ago
> None of these technologies allow you to exceed the available bandwidth. They just make use of the shared bandwidth more efficient. It's still a shared medium. The beam forming and such slice bandwidth availability spatially (that's what the cell network does too) so more people can use the shared medium by...not sharing it! It's not like AM radio that gets sent in all directions regardless of whether there is someone in a given direction to listen. > With fibre, every customer gets the full spectrum. Well by definition that's true whether fibre or copper, but that fibre or copper is itself aggregated into connections to upstream provider, so you're just kicking the problem down the road. You don't really get the full bandwidth end to end. As I said I think fixed wireless is an acceptable transitional technology but wired makes more sense longer term for most locations.
- defterGoose 6y ago
  >The beam forming and such slice bandwidth availability spatially (that's what the cell network does too) so more people can use the shared medium by...not sharing it! It's not like AM radio that gets sent in all directions regardless of whether there is someone in a given direction to listen. Nope. In theory yes, but unfortunately diffraction is going to get you every time if youre not transmitting in deep space.

by yarcob 6y ago

michaelmrose 6y ago

You are dead on. We are still transitioning from HD to 4k with 8k coming eventually. The difference in HD to 8k is 17x the bandwidth.

ksec 6y ago
>The difference in HD to 8k is 17x the bandwidth. The pixel is 17x, not bandwidth. Even Compressed RAW size dont scale linearly with pixel count. I dont have any experience with 8K, but compressing / encoding 4K with HEVC or AV1 tends to easier with fixed VMAF score than a comparatively low pixel count of 2K / 1080P. I would imagine the same if not better for 8K. And that is discounting the use of much better video codec like VVC which brings another 40 to 50% reduction in bitrate.
- michaelmrose 6y ago
  Good point.
AlexandrB 6y ago
Unless you're displaying on movie theatre sized screens, 8K seems like a waste of space/bandwidth. Even 4K is generally overkill for the typical living room. I think we're hitting the point with video resolution that music CDs hit with audio, where improvements in fidelity are largely outside the range of human perception. It's one of the reasons the music DVDs and SACDs never really caught on.
- elzbardico 6y ago
  Not sure about that. With large screens 55" at home and over I can see a difference between FHD and 4K, enough to know I am having network problems when the streaming service starts to downscale the resolution in a 4k video.
  - leetcrew 6y ago
    that could be the bitrate more than the resolution. streams are highly compressed. would be interesting to see whether you prefer 1080p bluray over a 4k netflix stream (I suspect yes).
- michaelmrose 6y ago
  1080p at 65 34ppi 4k at 65" 65ppi 8k at 65 135ppi This is well within what someone with good vision can see at for example 6-8 feet For a personal reference I could tell the difference in clarity at 8 ft between a 1080p 24" monitor and a 28"4k monitor. That is 157 vs 92 ppi on a screen a fraction of the size 5 minutes ago. I must imagine people making such claims have poor eyesight or are using optimum viewing charts as a proxy for distances wherein human vision was sufficiently acute instead of looking for themselves. For reference someone with good vision ought to be able to distinguish up to about 115ppi at 8ft according to this source. https://www.quora.com/What-is-the-highest-resolution-humans-can-distinguish https://www.quora.com/What-is-the-highest-resolution-humans-... The source seems valid despite the mixed bag that is quora. Especially since I and many others can verify this in 10 seconds. Edit: I wrote 43 instead of 34 by accident. 65" and 1080p = 34ppi
  - 6y ago
Syonyk 6y ago
> The difference in HD to 8k is 17x the bandwidth. Not practically. NetFlix will just compress it down to 3Mbit anyway like they do with 4k, but be able to call it "8k content!" and (probably) charge a premium for it.
gumby 6y ago
It remains to be determined. Quadrophonic sound did not replace the "good enough" stereo even though humans can move their heads. Of course an 8K TV is just as easy to set up as a 4K one, unlike a quadrophonic stereo. And the functionality of quadrophonic records became available as "surround sound" which some people do have. It's possible there are enough people who will appreciate the difference for 8K to become established. Personally I doubt it, but it's certainly possible. Another possibility is that your TV watches you and provides just a 4K or 4K-ish image unless you walk close to your TV at which point it displays a higher resolution image where you are looking. Possibly with some hint-driven mix of AI upsampling and more image data. The opposite could be true of course with 8K VR rigs in every home. I also doubt it, but it's quite possible. The 8K-production -> 4K result is well established and will remain even if my guesses above turn out to be correct. That needs a lot of bandwidth but not at the point of viewing.

mcny 6y ago

Level 3/CenturyLink/Lumen CEO reassured panicked investors and employees scared that their company would be worthless with 5G and beyond by basically saying that the last mile will increasingly become the last tens or hundreds of meters and that fiber is still the infrastructure on which these increasingly dense base stations depend on. And that the “edge computing” will likely live on the cabinets owned by the fiber provider. It makes sense to me. Just add more fiber and let people access them over whatever. My biggest gripe is we could choose to do away with licensing fees and spectrum auctions and open mm wave 5G to be something like Wi Fi but we are shortsighted as usual.

ksec 6y ago

>Where I live, a lot of people have 3G internet. Well, yes 3G is Shared Spectrum. >None of these technologies allow you to exceed the available bandwidth Exceed available bandwidth of what? Per Spectrum? Shannon–Hartley theorem? The whole point of 4G, and 5G, mentioned in the GP as Massive MIMO was that we could workaround those limits with more Antenna. Everything we are doing today and aiming to do in 3GPP Rel 17 in a few years time are literally impossible to even infer about in the early 2000s. When Massive MIMO, or it was known as Very large Array of Antenna was first published people called the idea "crazy". And CoMP, whether the marketing decide to call it 5.5G or 5.9G along with distributed antennas being worked on in 6G. There are no fundamental technical reason why we cant have a fully wireless Internet. Although there are many business and economical reason why this may never happen.

yarcob 6y ago
>>Where I live, a lot of people have 3G internet. >Well, yes 3G is Shared Spectrum. Sorry, I think I meant 4G, not 3G. It's marketed as LTE here. > Exceed available bandwidth of what? Per Spectrum? Shannon–Hartley theorem? No, not Shannon-Hartley. That's just a mathematical model. When EM waves propagate, they are subject to diffraction, which limits both the amount of information that can be transmitted per time interval, and also the spatial resolution of the transmission. Even with antenna arrays or distributed antennas you can't get past diffraction limits; you can just get closer to them. To get around diffraction limits, you need to use higher frequencies / shorter wavelengths. (Which has the side effect that you loose the ability of signals to go around / through obstacles, so you need a lot more cell towers.) We're at a point where new technologies just make different trade-offs (eg. shorter wavelengths for areas with lots of wireless clients vs. longer wavelengths for sparse areas). With a fibre connection, you don't need to make these tradeoffs; you just need to dig up the ground and you can have as much bandwidth between two points as you want.

vel0city 6y ago

A bit of a nitpick, but most residential fiber deployments are PONs. With a PON, a single fiber gets split into a lot of separate wavelength channels with prisms. It's still tons more usable bandwidth available than wireless. https://en.m.wikipedia.org/wiki/Passive_optical_network https://en.m.wikipedia.org/wiki/Passive_optical_network

gumby 6y ago

> None of these technologies allow you to exceed the available bandwidth. They just make use of the shared bandwidth more efficient. It's still a shared medium. The beam forming and such slice bandwidth availability spatially (that's what the cell network does too) so more people can use the shared medium by...not sharing it! It's not like AM radio that gets sent in all directions regardless of whether there is someone in a given direction to listen. > With fibre, every customer gets the full spectrum. Well by definition that's true whether fibre or copper, but that fibre or copper is itself aggregated into connections to upstream provider, so you're just kicking the problem down the road. You don't really get the full bandwidth end to end. As I said I think fixed wireless is an acceptable transitional technology but wired makes more sense longer term for most locations.

defterGoose 6y ago
>The beam forming and such slice bandwidth availability spatially (that's what the cell network does too) so more people can use the shared medium by...not sharing it! It's not like AM radio that gets sent in all directions regardless of whether there is someone in a given direction to listen. Nope. In theory yes, but unfortunately diffraction is going to get you every time if youre not transmitting in deep space.