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What 5G Will Mean for You

nytimes.com

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Re: What 5G Will Mean for You

#61

Post by pmontra »

vpkaihla wrote: post #14
pmontra wrote: post #6

> With 5G, downloading feature-length movies could take less than five seconds. > With 4G, downloading feature-length movies could take as long as eight minutes. Am I wrong in thinking that an operator would prefer to keep their antenna busy for only 5 seconds instead of for 8 minutes? If this is the case, if they have enough bandwidth to the antenna, they should try to move people to 5G quickly. But you still need 9…

What's a monthly cap?

https://en.m.wikipedia.org/wiki/Bandwidth_cap but the other answer captures the very spirit of the thing.

Re: What 5G Will Mean for You

#62

Post by f00fc0d3 »

kristoffer wrote: post #58
f00fc0d3 wrote: post #28

Earlier quoted context omitted.

This is totally wishful thinking. No one in industry has a slightest idea what 5G will be. We keep throwing fancy terms like eNodeB virtualization and then we have a reality check - LTE userplane cannot be virtualized due latency and performance reasons (LTE PHY on x86 - yeah, right...). Same goes to those mm waves with beamforming - no DSP (IP core) can handle it now and even soon. You need to stick with very expens…

It is possible to do compliant LTE phy on x86, of course it is not so energy efficient. Also x86 + fpga SoC is coming soon and could be interesting for that kind of purpose. Though I don't think baseband virtualisation will be something big in the near future. And LTE CC is not the necessarily a good way to get multi-Gbps due to radio complexity.

I have seen such projects - real LTE PHY algorithms are much more complex than stuff in 3GPP. You can write something 3GPP compliant in some simplified cases, but it would be totally useless in real network.

Secondly you don't really want to use FPGA for majority DSP processing in LTE PHY. Design cycles on FPGA are too slow and HLS techniques are still not trusted. Beside that x86+fpga are some kind of specialized stuff - you could just put a PCIe accelerator with some major wireless SoC.

Re: What 5G Will Mean for You

#63

Post by the_mitsuhiko »

f00fc0d3 wrote: post #59
the_mitsuhiko wrote: post #44

Earlier quoted context omitted.

> LTE userplane cannot be virtualized due latency and performance reasons Care to elaborate? I fail to see what the technical challenges are. Many services are already virtualized just on different layers if I understand this correctly (for instance Wifi calling).

HARQ loop in LTE is tight = 3 ms(3ms for ENB, 3ms for UE, 2 ms for air/RRH = 8 ms in total). It means that in those 3 ms you need to decode ack nacks in PHY, run scheduling and then send the data on other side of PHY. LTE PHY requires a lot of algorithms that doesn't fit well on x86 or general purpose HW like FFT or turbo decoding. Those usually are done in HW accelerators of baseband SOCs. x86 lacks also complex ari…

> HARQ loop in LTE is tight = 3 ms(3ms for ENB, 3ms for UE

Not sven sure how this is relevant. First of all the virtualization happens not on a global scale but quite local to whatever you can the base station in technical terms. Secondly there is no requirement in futuure standards to be as strict as LLE on that level. Lastly this is a few years out and obviously specialized hardware would be in place. It's kinda pointless to assume that this has to run on general purpose hardware.

Where does this idea come from that this virtualization has to happen on the other side of the world?

Re: What 5G Will Mean for You

#64

Post by bryanlarsen »

kbob wrote: post #57
bryanlarsen wrote: post #37

Earlier quoted context omitted.

Driverless cars need detailed and up-to-date map information. After you enter a destination it will need to download and/or update that information. It wouldn't be a safety issue, though. The car would not start driving to the destination until it had everything it needed.

So if you ever park in a dead zone, your car will have to be towed back to coverage?

If you're parked in a dead zone, and your car doesn't have manual controls, you should be able to return to the place you came from. Going some place else might be problematic. Tell the car to go home, hit the "stop" button once you're out of the dead zone, and then give it the new destination.

Re: What 5G Will Mean for You

#65

Post by f00fc0d3 »

the_mitsuhiko wrote: post #63
f00fc0d3 wrote: post #59

Earlier quoted context omitted.

HARQ loop in LTE is tight = 3 ms(3ms for ENB, 3ms for UE, 2 ms for air/RRH = 8 ms in total). It means that in those 3 ms you need to decode ack nacks in PHY, run scheduling and then send the data on other side of PHY. LTE PHY requires a lot of algorithms that doesn't fit well on x86 or general purpose HW like FFT or turbo decoding. Those usually are done in HW accelerators of baseband SOCs. x86 lacks also complex ari…

> HARQ loop in LTE is tight = 3 ms(3ms for ENB, 3ms for UE Not sven sure how this is relevant. First of all the virtualization happens not on a global scale but quite local to whatever you can the base station in technical terms. Secondly there is no requirement in futuure standards to be as strict as LLE on that level. Lastly this is a few years out and obviously specialized hardware would be in place. It's kinda po…

Future standards will be even more tight, 5G working assumption is 1 ms HARQ loop.

Where you got the idea that I assume the ENB has to be on other side of the world ?

Re: What 5G Will Mean for You

#66

Post by mafribe »

jerf wrote: post #52
mafribe wrote: post #36

Earlier quoted context omitted.

data and transport layers are almost always intermingled In what sense other than NATing, which has been a stop-gap measure to deal with IPv4 address shortage? TCP/UDP sit on top of the network layer, not the data (link) layer. And the two main requirements that TCP/UDP make of the network layer is (1) that all network layer connected devices (interfaces) have a unique address and (2) you can send packets between any…

That's still the beautiful model you're referencing, not the reality of networking. If you saw what the actual network devices in the stack were doing, you would be... less impressed by the beauty, let's say. But they work, and they're fast. That has beauty of its own. And I mean real network hardware through which the packets your received these words are, too, not just abstract theoretical "somebody's got something…

     If you saw what
In a nutshell, what are networking devices doing that mixes network and transport services (other than NATing)?

Re: What 5G Will Mean for You

#67

Post by the_mitsuhiko »

f00fc0d3 wrote: post #65
the_mitsuhiko wrote: post #63

Earlier quoted context omitted.

> HARQ loop in LTE is tight = 3 ms(3ms for ENB, 3ms for UE Not sven sure how this is relevant. First of all the virtualization happens not on a global scale but quite local to whatever you can the base station in technical terms. Secondly there is no requirement in futuure standards to be as strict as LLE on that level. Lastly this is a few years out and obviously specialized hardware would be in place. It's kinda po…

Future standards will be even more tight, 5G working assumption is 1 ms HARQ loop. Where you got the idea that I assume the ENB has to be on other side of the world ?

> Future standards will be even more tight, 5G working assumption is 1 ms HARQ loop.

That's just to the base station, no? How does that in any way apply to what you transmit over your network?

> Where you got the idea that I assume the ENB has to be on other side of the world ?

Because your comment about latency implied that.

Re: What 5G Will Mean for You

#68

Post by kristoffer »

f00fc0d3 wrote: post #62
kristoffer wrote: post #58

Earlier quoted context omitted.

It is possible to do compliant LTE phy on x86, of course it is not so energy efficient. Also x86 + fpga SoC is coming soon and could be interesting for that kind of purpose. Though I don't think baseband virtualisation will be something big in the near future. And LTE CC is not the necessarily a good way to get multi-Gbps due to radio complexity.

I have seen such projects - real LTE PHY algorithms are much more complex than stuff in 3GPP. You can write something 3GPP compliant in some simplified cases, but it would be totally useless in real network. Secondly you don't really want to use FPGA for majority DSP processing in LTE PHY. Design cycles on FPGA are too slow and HLS techniques are still not trusted. Beside that x86+fpga are some kind of specialized st…

Modern x86 is quite competent as DSP using AVX. I think you are exaggerating. I have worked with LTE baseband as well, but admittedly never done an x86 LTE PHY. pCell claims to be doing quite complex network mimo LTE stuff on x86, still mostly vaporware though.

Regarding FPGA, of course you don't do the complete implementation in it, you accelerate the low level stuff, FFTs, coding, etc, as are already done in all baseband dsps.

Re: What 5G Will Mean for You

#69

Post by the_mitsuhiko »

kbart wrote: post #48
the_mitsuhiko wrote: post #41

Earlier quoted context omitted.

That is very wrong. There is for instance a lot you can do with 4G that was not possible with 3G. With 3G the more devices the worst the throughput for all. LTE time slices and runs qos for all devices so it does not degrade with increasing device count. However there is a general linit in the the cell which is hard to raise making it uninteresting as a replacement for fiber. Future standards want to remedy this.

I agree that there a lot of technological advances and infrastructure will be much more efficient and robust, but I assume this article was what 5G means for me , not my carrier. Currently (good) carriers solve congestion problem by installing more and smaller cells which is costly solution and that's why their drive to 5G is understandable.

> but I assume this article was what 5G means for me

Why would that not be for "you"? When LTE rolled out in my country my usage pattern shifted. I paid up for higher/unlimited data allowance and can truly work remotely now unhindered. That includes data and latency critical tasks.

Re: What 5G Will Mean for You

#70

Post by [deleted] »

kbart wrote: post #48
the_mitsuhiko wrote: post #41

Earlier quoted context omitted.

That is very wrong. There is for instance a lot you can do with 4G that was not possible with 3G. With 3G the more devices the worst the throughput for all. LTE time slices and runs qos for all devices so it does not degrade with increasing device count. However there is a general linit in the the cell which is hard to raise making it uninteresting as a replacement for fiber. Future standards want to remedy this.

I agree that there a lot of technological advances and infrastructure will be much more efficient and robust, but I assume this article was what 5G means for me , not my carrier. Currently (good) carriers solve congestion problem by installing more and smaller cells which is costly solution and that's why their drive to 5G is understandable.

[deleted]
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