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NBN download speeds in practice: fast enough to access UHD?


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1 hour ago, mello yello said:

question still is ... am i getting 2160 if the little window displays 2160 ?

im guessing YES (but its limited )

Netflix works by buffering so if you've got a good 10Mbps connection then it could do HD for a while then bump it up to UHD for a short term once you've amassed enough data. Interesting the demo loops seem to do UHD while movies all go 1080p (perhaps the demo loops are buffered?). Netflix is experimenting with users being able to buffer whole movies locally so its possible shorter clips are already.

To answer your question, given that watching a movie that constantly switches between resolutions would probably cause all sorts of occasional screen flicker, I'd assume Netflix keep the resolution constant on the fly even though the input signal isn't. So if its seeing you can occasionally get UHD then it defaults to that resolution, but if its only getting 1080p then it just scales up everything by 4 pixels (to put it simply) and your TV is none the wiser. To the view the image just gets a tad blurrier (or crisper) at points.

0.02

Regards

Peter Gillespie

 

1 hour ago, alanh said:

The speed drops off very quickly with distance on copper cables, particularly when every property is using it at the same time, which will be typical in business hours for FTTN.

Business hours are essentially off peak hours. Residential use only spikes after 5pm usually.

Regards

Peter Gillespie

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1 hour ago, mello yello said:

thanks Peter, so that number in the top left is the actual current resolution

I'm like you, don't really know though. Just top clarify the 'actual resolution' might be UHD res, but that might be made up from a 1080p signal that has been blown up, if you know what I mean. I should probably withdraw the comment, as i really don't know.

Regards

Peter Gillespie

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13 hours ago, mello yello said:

im getting Nutflakes UHD 4K with a 10Mbps linespeed ADSL2+

just the odd nature/flowers/waterfalls thing though, the proper movies revert to 1080p (if i understand how the info bar works)

am i correct in assuming the info in the top left hand corner that displays time into movie/5.1 sound/language and resolution is the actual resolution being streamed and not its actual native resolution ?

Yes.  If you have a Netflix application that provides a number in the top left hand corner of resolution information about the current Netflix stream (e.g. 384, 480, 720, 1080, or 2160) that information reflects the incoming Netflix video resolution. As you have experienced, it can change on the fly.

I think you're doing surprisingly well, mello, to be able to get 2160p Netflix even for short periods of time with only a 10Mbps line speed!

 

If there is a drop in download speed capability, then Netflix can seamlessly switch the source of the video frames to a lower resolution format in its library. There is no judder or other apparent discontinuity when the change to a smaller frame size takes place. [Edit: That's been my experience when simulating a lower download capacity by starting up a separate download, or by moving the wi-fi modem well away from devices accessing it.]

Netflix have been experimenting with using different bitrates with different source material; so that less demanding material that doesn't need as high an encoding rate to maintain quality can be encoded at a lower rate. For example, as stated in the Netflix Blog of 14 December 2015 ( http://techblog.netflix.com/2015/12/per-title-encode-optimization.html ):

Quote

Per-title encoding allows us to deliver higher quality video two ways: Under low-bandwidth conditions, per-title encoding will often give you better video quality as titles with “simple” content, such as BoJack Horseman, will now be streamed at a higher resolution for the same bitrate. When the available bandwidth is adequate for high bitrate encodes, per-title encoding will often give you even better video quality for complex titles, such as Marvel's Daredevil, because we will encode at a higher maximum bitrate than our current recipe. Our continuous innovation on this front recognizes the importance of providing an optimal viewing experience for our members while simultaneously using less bandwidth and being better stewards of the Internet.

On a technical matter you have been discussing with pgdownload, in my reading of other forums (and of explanations by Netflix) I have not seen any reference to packaging lower resolution frames as a higher resolution to assist continuity (i.e. in effect offering low resolution material in an upscaled form). It appears there is simply one video encoding per title in the Netflix library for a given resolution format and codec.* I conclude it is up to the subscriber's Netflix app (and if necessary the platform with which it operates) to adapt dynamically to any change in incoming stream resolution format. 

___

* Edit. Correction: some additional encodes are done to suit certain resolution-capped devices. As stated in the blog I linked to above:

More specifically, we design additional optimal per-title bitrate ladders tailored to 480p and 720p-capped devices.  While these extra encodes reduce the overall storage efficiency for the title, adding them ensures that our customers have the best experience.
 
Edited by MLXXX
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5 hours ago, alanh said:

The speed drops off very quickly with distance on copper cables, particularly when every property is using it at the same time, which will be typical in business hours for FTTN.

Alanh, can you please elaborate on what you mean here?

Each premises in a street that connects to an FTTN cabinet will connect via the existing copper cable, i.e. a separate wire for each connection to the cabinet. That's a different topography to HFC where the one coaxial cable may serve, and be shared by, an entire street.

Are you suggesting there can be expected to be a speed bottleneck in the cabinet itself? Or are you suggesting there will be material interference between the separate copper wires during periods of peak use?

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a very detailed, appeciated and comprehensive reply MLXXX, that does appear to be the case

im learning as i go (but there is only so far that i will go)

example, i think ive stopped talking to cwt when he recommended a PS4 lol

 

Edited by mello yello
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For what its worth, a week ago I got connected to the NBN FTTN, and whilst its way to early to make a call on whether FTTN is going to deliver an acceptable bandwidth long term, on a 50mbps plan, download speed tests using my wifi network, indicate a fairly consistent connection at around 45mbps.  I am located close to the Rockhampton CBD about 280 metres from the nearest node.  I am advised that about 30% of premises in this area have been connected with the previous service an ADSL 2+. 

I was previously connected to a FTTP service in nearby Gracemere (courtesy of renting in a new sub-division).  At that location on a 50mbps plan, the FTTP result was roughly the same as I am experiencing  with FTTN in Rockhampton.   I was also advised by the local Optus consultant that it would be better to initially connect with a 25mbps service at my new location, as speeds during the NBN transition phase could not be guaranteed.

So far so good, but a lot of stuff can happen as more customers come on line.  

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19 hours ago, mello yello said:

example, i think ive stopped talking to cwt when he recommended a PS4 lol

Going with your keen eye for value mello :) Heartening you have raised your sights to marantz :D

I wonder if you have a better than average processor in your panel that can hold more in its buffer after reading what MLXXX said ; something to do with its memory allocation ? pure speculation from a pc noob here ..

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A lot faster processor than what a previous model would have had mello ; so higher throughput possibly ? Anything is better than the 3mbps odd I get now :bye:

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On 09/08/2016 at 5:47 PM, cwt said:

A lot faster processor than what a previous model would have had mello ; so higher throughput possibly ? Anything is better than the 3mbps odd I get now :bye:

not just the processor, it beats anything i have seen hands down, but still getting the occasional 2160 on the nature films ( 1080 with standard dialogue movies though ...havent managed to crack the 2160 barrier with those yet) ...dont know exactly why, would be interesting to hear if a 6 series can achieve the same

just a little OT sidetrack ...

i replaced a UA55F7100 ( 7 series back then is no slouch either, they were part of the 7/8/9 batch, with 200Hz unlike the 100Hz of current 7 Series which are more of a tarted up 6 series ) , anyway completely blows the 55inch HD out of the water, just as a comparison

out of curiosity i went back in to have a look at what i thought was a good (if not one of the best ) HD 65inch panels ... the Sony 65W850C, which i was considering seeing the state of actual 4K content available and most of my viewing in SD/HD anyway ...

even though the Sony looked very good on the day, and very close to the KS9000 running HD content, it now looked washed out and blurry compared to what i have been using for about a week or so

even the OLED demos didnt look as good as they did on the days i went goodwill hunting

 

im happy, cost a pretty, but it is a flagship ;-)

 

(somebody asked for a review, thats about the size of my technical expertise, how it actually looks, so thats it basically ..."im no tech-head, but i know what i like")

 

probably will have to give up eating/smoking/driving after the invoice comes in

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I seem to be doing alright tonight Mello, my last speed test indicated I was getting a whopping 1.4 Megabits/second download speed.

Things are looking up ! :lol:

 

Sorry ,  I just rechecked, it is now at 311 Kilobits/second.

C.M

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8 hours ago, mello yello said:

not just the processor, it beats anything i have seen hands down, but still getting the occasional 2160 on the nature films ( 1080 with standard dialogue movies though ...havent managed to crack the 2160 barrier with those yet) ...dont know exactly why, would be interesting to hear if a 6 series can achieve the same

 

Struck me that those earlier 7/8/9 sammys and the sony of course wouldnt have the HEVC decoder you now have that is necessary for any 4k streaming - thats good insurance :ahappy:

 

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On 8/8/2016 at 7:11 PM, pc9 said:

For what its worth, a week ago I got connected to the NBN FTTN, and whilst its way to early to make a call on whether FTTN is going to deliver an acceptable bandwidth long term, on a 50mbps plan, download speed tests using my wifi network, indicate a fairly consistent connection at around 45mbps.  I am located close to the Rockhampton CBD about 280 metres from the nearest node.  I am advised that about 30% of premises in this area have been connected with the previous service an ADSL 2+. 

I was previously connected to a FTTP service in nearby Gracemere (courtesy of renting in a new sub-division).  At that location on a 50mbps plan, the FTTP result was roughly the same as I am experiencing  with FTTN in Rockhampton.   I was also advised by the local Optus consultant that it would be better to initially connect with a 25mbps service at my new location, as speeds during the NBN transition phase could not be guaranteed.

So far so good, but a lot of stuff can happen as more customers come on line.  

Thanks for this info, pc9. Reports of real world experience are very helpful.

I note that an important factor with FTNN in Australia and more customers getting their phone lines connected to the NBN is the use of "vectoring", a technology for continuously measuring and cancelling out [or very substantially reducing] adjacent line crosstalk. (This 2011 article includes a graph of "typical" speed improvements from using vectoring: http://insight.nokia.com/boosting-vdsl2-bit-rates-vectoring )

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Good article - all the more interesting in view of my local property connection which consists of an exposed skinny coaxial cable with a horrible kink, but getting a consistent 45mbps...............the wonder of it all! 

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http://www.abc.net.au/news/2016-03-01/manning-what-went-wrong-with-the-nbn/7210408

The latest leaked NBN document gives us more insight into the project which was meant to be about "nation building", but which is now turning into a politicised quagmire, writes Paddy Manning. Yesterday's leaked internal document revealing that the NBN's rollout of fibre-to-the-node has been well behind schedule is further confirmation that Malcolm Turnbull's version of the NBN is proving to be much more expensive to deliver than was originally hoped.

The latest leak confirms the copper-based fibre-to-the-node component of the MTM - which will bring fibre through to fridge-sized cabinets on many street corners - is proving difficult. One of the well-known disadvantages of fibre-to-the-node is that the nodes require power. That there have been delays due to negotiations with electricity suppliers was predictable and can only be considered a failure of network planning.

There is no doubt Labor's NBN would have sold for more, improving the return for taxpayers.

Again, this should not be a surprise: one of NBN's own directors, Simon Hackett, said last year that fibre-to-the-node is a "dud", and NBN has already started trialling faster technologies that will rely on bringing fibre closer to the home, to what is known as the distribution point or "fibre-to the-curb", potentially replacing fibre-to-the-node altogether but increasing the rollout cost again.

The upshot is that we have a NBN which gives some lucky home and business owners a fibre-optic connection courtesy of Labor's abandoned rollout, while the rest of us wait for our HFC cable to be upgraded or make do with a much slower copper-based connection that will probably need to be replaced.

:ermm:

JSmith :ninja:

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1 hour ago, JSmith said:

The latest leaked NBN document...

jsmith, I see you have reproduced part of an article posted on the ABC website on 1st March. There have been many articles complaining about the rate and cost of the NBN rollout.  And many bemoaning the limited maximum data rates in theory and practice.

The focus of this thread is whether people are finding NBN download rates fast enough in practice to access UHD [streaming]. It seems likely that for subscribers to a fibre to the node connnection the vast majority of such subscribers should  be able to access UHD streaming, provided the capacity in the rest of the network i(including the capacity paid for by their ISP) is sufficient. A key reason for the likely success of FTTN for people a few hundred metres from a node cabinet is the use of vectoring to combat crosstalk from copper telephone wires serving other subscribers. Another very important factor is avoiding too great a distance for the run of copper telephone wire from a subscriber to a node cabinet. I've been assuming that densely populated areas will be provided with relatively closely spaced cabinets. Less densely populated areas might not be so fortunate.

A variable I'm interested in knowing about is how many people for one reason or another cannot consistently obtain at least say 20Mbps* (preferably 25Mbps) download speed through the NBN (having signed up for a tier 2 or higher plan). Or conversely, how many are consistently achieving that speed without difficulty.

I know there have been a number of anecdotal reports at Whirlpool forum but a lot of these lack detail. Hopefully people who post their experiences here will explain their circumstances sufficiently, e.g. what NBN connection type they have, the name of their ISP, the tier (download and upload speeds) they have signed up for, and the sorts of speeds they've been experiencing at different times.  

Ideally there'd be official detailed surveys of actual NBN speed performance, but I haven't seen any announcement such surveys are planned.

__________

* In practice, Netflix Australia does not appear to need 25Mbps for consistent viewing at 2160p of at least some of their UHD titles, despite Netflix recommending a minimum 25Mbps download capability for UHD.  

Edited by MLXXX
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57 minutes ago, MLXXX said:

* In practice, Netflix Australia does not appear to need 25Mbps for consistent viewing at 2160p of at least some of their UHD titles, despite Netflix recommending a minimum 25Mbps download capability for UHD.  

 

Not sure anywhere like 25Mbps is needed. There's a handy conversion website here

I had a look at some episodes and 2160p (10 bit) encoded by HVEC 265 used about 2.2 Gb/hr. Using the conversion chart this equate to around 5 Mbps 

That said I looked at actual Jessica Jones Netflix 2160p  HVEC 264 downloads and they were encoded at around 16Gb/hour. Allow a 40% improvement if you go to HVEC 265 and you get around 10Gb/hr or 23 Mbps

Clearly there are other factors at play here (something has to give if the resolution stays at 2160p) but we do know that Netflix essentially distribute multiple copies of the same show to each of its nodes, for each resolution involved. I wouldn't be surprised to find that there are actually 2 or more 2160p versions that mean a drop in PQ as the bitrate drops. 

The above figures suggest 25Mbps is indeed needed to get the full 2160p experience, but that 10Mbps could easily give a credible 2160p view that is hardly noticibly different on most TVs by most people. The question for netflix would only be as the available bitrate decreases is it at what point does the compressed 2160p become poor enough that switching to max quality 1080p provides a better image?

Regards

Peter Gillespie

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17 minutes ago, pgdownload said:

I wouldn't be surprised to find that there are actually 2 or more 2160p versions that mean a drop in PQ as the bitrate drops. 

There is nothing to that effect I have seen in fairly detailed descriptions Netflix have published about how they create their libraries. [As a matter of detail,  Netflix do state they create extra versions for 480p and 720p resolution limited devices to provide a higher bitrate alternative for such devices, because even with a fast internet connection such devices are unable to access a high bitrate higher resolution version in the library.]

I would agree though that in theory it would be open to Netflix to create a reduced bitrate 2160p version in addition to their standard 2160p version. 

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2 hours ago, MLXXX said:

The focus of this thread is whether people are finding NBN download rates fast enough in practice to access UHD [streaming]. 

Not with all that quality copper out there... ;)

I thought this part of that article was also interesting;

HFC trials so far have been encouraging and there is no doubt that the planned DOCSIS3.1 technology can deliver superfast internet speeds, but it will not be cheap and the major rollout will not begin until 2017-18.

There's many users on WP who are experiencing much slower speeds than expected on "NBN" accounts... but we all know it's not really a proper fibre connection, so why it's called "NBN" is beyond me.

JSmith :ninja:

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