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Re:How the BBC and ITV are fixing delays on World Cup live s... by untog on Friday July 13, 2018 @03:58PM (#17526177)
It's really interesting to see the tech being deployed to fix this problem. But it also amazes me how complicated we've managed to make things. In the UK in particular - just a few years ago the vast majority of people received their TV through over-the-air broadcast. It's instant and scales infinitely, kind of beautiful simplicity, technically speaking.

Sports are a good test case, not just for latency but sheer demand. I worry that we'll face some kind of natural disaster in the not too distant future that'll make us wonder why we abandoned the resilience of OTA broadcast.

Re:How the BBC and ITV are fixing delays on World Cup live s... by laumars on Friday July 13, 2018 @04:30PM (#17526421)
I don't disagree with your point per se but you are over simplifying things. Here is my take after working in the industry:

> It's instant

It isn't. There are still latency delays with digital encoders, transmitter hops, etc even with OTA signals. It's just the equipment has gotten so good over the years that the latency has been pushed right down but it did used to be a lot worse. The same will happen with IP streaming given time.

> scales infinitely

It doesn't. You need geostationary satellites / multiple transmission towers, and all that only provides you a finite number of channels. In fact digital streams are actually much cheaper to scale up, which is why so many broadcasters are moving into this territory (and why I currently have a job)

> kind of beautiful simplicity, technically speaking

Superficially yes. But if you spend any amount of time around OTA broadcasters (as I have) you'll see there is a hell of a lot of complexity hidden from sight. In fact since OTA broadcasts are still digital streams served from content stored in digital formats, a lot of the technology used for internet streaming is the same for OTA broadcasts. So there is an argument for the simplicity of just serving that digital stream via IP rather than radio waves (or are you suggesting we go back to analogue as well? Because that also introduces a lot of complexity but of a different nature, like having to giant robotic cabs filled with hundreds of magnetic taps that all have to be wound to the right point; and a dependency on the postal service delivering those tapes since you now cannot just download assets from the content owners).

I'm not saying there isn't a lot of new complexity with IP streaming but I do think it's more pronounced because:

1/ we work in IT so follow the technology more closely than we do for OTA broadcasting

2/ it's still a relatively young industry so there are a lot warts that haven't been cleaned up (much like how OTA broadcasting used to be a lot less polished when the technology there was still evolving).

Re:How the BBC and ITV are fixing delays on World Cup live s... by skellera on Friday July 13, 2018 @06:28PM (#17527410)
I believe they were referring to number of receivers of the broadcast for scale. Distance from the tower being the limitation.
Re:How the BBC and ITV are fixing delays on World Cup live s... by laumars on Friday July 13, 2018 @07:00PM (#17527594)
That's "just" a problem with unicast though. Lots of different media houses are working on getting multicast support over the internet, by which point IP streams will behave a lot more like OTA's one-to-many relationship.

I couldn't say how close they are to getting that working - nor if it even is possible - because I don't work on that specific side of things. But I do know there used to be multicast networks over the internet back in the 90s (IIRC David Bowie even streamed one of his concerts over it) so it strikes me as a solvable problem.

Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Saturday July 14, 2018 @03:17AM (#17529239)
Bbc did multicast 20 years ago, and with most uk households on one of half a dozen isps it would be possible.

However multicast struggles over wifi and 4g.

A CDN edge box in each exchange would probably solve the problem.

Re:How the BBC and ITV are fixing delays on World Cup live s... by dmurray on Friday July 13, 2018 @06:35PM (#17527467)
Yeah, for events like the World Cup "scale" means sending the same broadcast to millions of receivers. That's already an unusual requirement, though. Major sporting events constitute the biggest use case, and perhaps even those will require something different in future if the next trend is something more interactive: VR or user controlled camera angles.
Re:How the BBC and ITV are fixing delays on World Cup live s... by untog on Friday July 13, 2018 @06:56PM (#17527575)
> sending the same broadcast to millions of receivers. That's already an unusual requirement, though

Broadcast television isn't particularly unusual, surely. Millions of people watch live, primetime TV every day.

Re:How the BBC and ITV are fixing delays on World Cup live s... by blowski on Friday July 13, 2018 @08:45PM (#17528058)
In the UK, typical peak usage is around 5 million for the same program at the same time. The World Cup was more than 30 million.
Re:How the BBC and ITV are fixing delays on World Cup live s... by untog on Friday July 13, 2018 @11:17PM (#17528604)
Sure, but my point was that five million receivers is "millions of receivers", and is an everyday occurrence.
Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Saturday July 14, 2018 @03:15AM (#17529228)
This is a legacy way of consuming material. More and more are using on demand first.

However the use case of live sport - especially football in the uk - is massively different. This means the platforms have to scale to 20 million plus live streams (that's say 100tbit and 5 second latency) for a once in 4 year event.

Re:How the BBC and ITV are fixing delays on World Cup live s... by adreamingsoul on Friday July 13, 2018 @06:03PM (#17527212)
Well said.
Re:How the BBC and ITV are fixing delays on World Cup live s... by outworlder on Friday July 13, 2018 @04:24PM (#17526378)
Indeed, that's a bit silly. WE are calling these things 'broadcast', while most implementations are really unicast. This works really great for things like netflix, where you can start watching whatever you want, independently.

But in this case we really want actual broadcasts. Talk about square pegs and round holes...

Re:How the BBC and ITV are fixing delays on World Cup live s... by harlanji on Friday July 13, 2018 @10:53PM (#17528535)
VOD = video on demand, unicast is good. Live = stream, multicast is good. The 1.5 second multicast estimate for next Olympics from BBC sounds reasonable based on my experience working with signalling and now live straming systems.

Good read around the steps and impact around buffering introducing delay. My programmer brain said “sounds like the receiver should control flow into its encoder”... so is it that it’s too conservative a buffer, or the encoding algorighms actually need that much buffer to get economy?

Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Saturday July 14, 2018 @03:20AM (#17529247)
With PPP encoding you can get end to end h264 latency down to 7 or 8 frames while maintaining a cracking picture quality.
Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Friday July 13, 2018 @04:09PM (#17526253)
Still do. While just over 1 million watched the last BBC england game on iplayer (before it crashed), at least 20 million were watching on BBC One.

Everything else makes perfect sense to broadcast, but live -- especially zero-latency live -- over unicast http calls? Ridiculous. A shame the BBC's multicast trials never took off.

Re:How the BBC and ITV are fixing delays on World Cup live s... by blntechie on Friday July 13, 2018 @10:45PM (#17528511)
In India , we had a 9.7 million concurrent streams record recently for a cricket game with a service called Hotstar. The stream at least for me was ahead of Cable TV, not sure if they delayed the TV broadcast to account for live streaming delay to make it appear live.
Re:How the BBC and ITV are fixing delays on World Cup live s... by djhworld on Friday July 13, 2018 @04:11PM (#17526278)
> While just over 1 million watched the last BBC england game on iplayer (before it crashed), at

3.8 million according to https://www.theguardian.com/media/2018/jul/08/england-world-...

Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Friday July 13, 2018 @04:15PM (#17526308)
That's 3.8 total, not concurrently

I.e. people tried iplayer, saw how crap the experience was (in this niche case), then found a TV or pub with TV to watch it on.

Re:How the BBC and ITV are fixing delays on World Cup live s... by djhworld on Friday July 13, 2018 @04:23PM (#17526366)
Ah concurrents.

In this case the stream went down in the last 5 minutes of the match, which is still bad, but not as bad as YouTube TV earlier this week!

https://twitter.com/YouTubeTV/status/1017121393857556485

Re:How the BBC and ITV are fixing delays on World Cup live s... by wayanon on Friday July 13, 2018 @06:04PM (#17527225)
Or found the pub was using iPlayer too..
Re:How the BBC and ITV are fixing delays on World Cup live s... by philjohn on Friday July 13, 2018 @04:17PM (#17526327)
The problem is we only have a finite amount of spectrum available, and people like choice, so there are more channels than there are slots in the airwaves for them to be broadcast.

Just like the phones in the UK will, in the not too distant future, move from POTS to a fully packet switched network, so too will television, especially once at least superfast (24Mbps and up) broadband is available to all - there are already rumblings that Sky would like to move to IPTV instead of having to bounce their signals off a satellite.

Re:How the BBC and ITV are fixing delays on World Cup live s... by reaperducer on Friday July 13, 2018 @04:55PM (#17526628)
As is so often the case in life, it's a case of squeezing a balloon. In order to get more of one thing, you have to have less of another.

In this case, to have more reliability in transmission, you have to have fewer choices.

I can't speak to the UK's digital situation, but in the U.S. there are 50 channels available in a theoretical city. Assuming that digital has fewer co-channel issues than analog (most of my TV experience is analog), that means 25 signals. On those 25 signals, some broadcasters squeeze up to 10 channels, which all look like garbage. For a decent picture, it's closer to four — maybe five.

So that means 100 to 125 theoretical OTA channels.

If people could actually receive 125 OTA channels with good programming on them, or even the same content as is offered on cable/satellite, I believe many would drop pay TV in a heartbeat, and wouldn't be forced to also scrounge for content on Netflix and YouTube and Prime Video.

If anyone has information on the theoretical maximum number of TV channels possible in a single location in the UK, I'd like to hear about it.

Re:How the BBC and ITV are fixing delays on World Cup live s... by mikeash on Friday July 13, 2018 @05:45PM (#17527011)
I’d be shocked if 125 good channels would convince people to give up on-demand streaming services. 125 really is not a whole lot when you need to satisfy everybody, and the need to obey someone else’s schedule really sucks.
Re:How the BBC and ITV are fixing delays on World Cup live s... by thaumasiotes on Friday July 13, 2018 @06:53PM (#17527560)
> just a few years ago the vast majority of people received their TV through over-the-air broadcast. It's instant and scales infinitely, kind of beautiful simplicity, technically speaking

"Scales infinitely" is underspecified. Over-the-air broadcast scales well with the number of people who want to receive a particular broadcast. It scales very poorly on some other dimensions:

- Over-the-air suffers from congestion when many parties want to send a broadcast simultaneously. There's only so much spectrum. In a wired network, you can just add more wires.

- Over-the-air doesn't scale well at all when people want to receive the same broadcast from farther away. In a wired network, you can use longer wires, or relay data from one wire to another wire. (Relays will work for wireless too, but they make congestion that much worse.)

Re:How the BBC and ITV are fixing delays on World Cup live s... by mattmanser on Friday July 13, 2018 @04:28PM (#17526401)
That's not true in some ways, TV requires a huge number of transmitters and is limited to a few channels, where the internet has a virtually infinite number of channels.

Even now it's digital here in the UK I believe each of the 5(?) muxes can only support tens of channel each.

Airwaves TV might scale easily but can only send a proportionally small amount of information, but the internet send a vastly larger amount of data per second, but struggles when everyone wants the same data at once.

Re:How the BBC and ITV are fixing delays on World Cup live s... by 21 on Friday July 13, 2018 @06:37PM (#17527474)
> It's instant and scales infinitely, kind of beautiful simplicity, technically speaking.

I'm not so sure. When I had analog over-the-air TV, in a non-capital city, I remember quite a few times when most of the channels would go down during a storm.

Re:How the BBC and ITV are fixing delays on World Cup live s... by djhworld on Friday July 13, 2018 @04:08PM (#17526247)
The interesting element of the online streaming is the rise of people watching on their phones/tablets, where getting a traditional OTA signal isn't possible.
Re:How the BBC and ITV are fixing delays on World Cup live s... by sova on Friday July 13, 2018 @04:10PM (#17526262)
In Japan many cell phones have antennas to pick up OTA signals
Re:How the BBC and ITV are fixing delays on World Cup live s... by reaperducer on Friday July 13, 2018 @05:00PM (#17526657)
Korea, too. Probably some other countries. I remember the PSP had an optional OTA antenna.

There have been several attempts at doing the same thing in the U.S., but none of them ever worked out for various reasons. Often it was because of the expense of upgrading the tens of thousands of TV transmitters across the country.

This one died in 2011: https://en.wikipedia.org/wiki/MediaFLO

In a small country with more centralized control of broadcasting and less territory to cover like Japan and Korea, it's much easier.

Re:How the BBC and ITV are fixing delays on World Cup live s... by sushid on Friday July 13, 2018 @05:40PM (#17526971)
Yup, I remember when I thought having my Motorola RAZR was the epitome of cool, people in Seoul would flip up their seemingly dumber phones and stream crystal clear HD TV in the subway.
Re:How the BBC and ITV are fixing delays on World Cup live s... by kevin_thibedeau on Friday July 13, 2018 @06:05PM (#17527227)
For South Korea it's not normal HDTV but a special broadcast for mobile devices, DMB [1]. It was only recently updated to support 720p in favor of 240p. They aren't picking up the domestic ATSC signals. The Japanese mobile video system is a similar separate broadcast.

https://en.wikipedia.org/wiki/Digital_multimedia_broadcastin...

Re:How the BBC and ITV are fixing delays on World Cup live s... by throwaway2048 on Friday July 13, 2018 @06:02PM (#17527195)
Just a sidenote, there is really nothing preventing that techically speaking, after cellular signals are OTA, and handheld tvs used to be a thing.
Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Friday July 13, 2018 @04:11PM (#17526277)
Indeed. And it's not good.

https://www.bbc.co.uk/news/entertainment-arts-44722812

Actors have vented their fury at two audience members who watched England's World Cup penalty shoot-out on their phones in the front row of a musical.

Titanic The Musical actor Niall Sheehy said the women "not only followed the penalty shootout on their phone, but also said 'yesss' on each goal scored".

He declared: "You are the most ignorant audience members I have ever had the misfortune to perform in front of."

Re:How the BBC and ITV are fixing delays on World Cup live s... by jrockway on Friday July 13, 2018 @04:32PM (#17526440)
You're blaming technology for social problems. For every person that interrupts a play, there are 10 people quietly watching on their train home... turning wasted time into time enjoyed.

Rude people are always going to be rude, and we shouldn't worry about the technology that enables them to do so. If they couldn't watch soccer during a musical, they'd just be coughing loudly or rummaging around in their pockets looking for a mint or having a too-loud "private" conversation with the person next to them.

Phones have changed nothing.

Re:How the BBC and ITV are fixing delays on World Cup live s... by comex on Friday July 13, 2018 @06:03PM (#17527217)
I’m not confident it’s actually true that “phones have changed nothing”. They’ve certainly increased the variety of distractions one can access from a theater seat, as well as the ease of accessing them. But it’s also clear that most people have enough self-control to avoid using their phones for the duration of a musical, so it’s reasonable to blame those who don’t rather than blaming the technology. (This is distinct from the longer-term phenomenon of phone addiction, where there’s more room to blame the technology’s addictive qualities…)
Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Sunday July 15, 2018 @05:51AM (#17534552)
This is the same argument that people use about "don't blame guns, it's people that are the problem"

Seems to me that theatres (and cinemas) should be putting passive farady cages to block signals coming in, I'd pay extra for that.

Re:How the BBC and ITV are fixing delays on World Cup live s... by repolfx on Saturday July 14, 2018 @05:56AM (#17529636)
Typical actors. A profession with a more entitled attitude is hard to find. You see it too in how often actors make grandiose political or social pronouncements and expect everyone to care.

They got paid to perform a play. There is no more obligation for the audience members to pay attention than there is for someone to eat all the food on their plate at a restaurant, or use a device they bought every day. If the women weren't disrupting the other audience members then the actors shouldn't have cared (and if they were, that's a problem for the house staff to sort, not them).

If actors understood that it's not the audience who is privileged to watch them act, it's them who are privileged to be paid to play make-believe on stage, the world would be a much better place.

Re:How the BBC and ITV are fixing delays on World Cup live s... by mpg33 on Friday July 13, 2018 @04:10PM (#17526266)
Same with radio in cars. It just works.
Re:How the BBC and ITV are fixing delays on World Cup live s... by laumars on Friday July 13, 2018 @05:00PM (#17526652)
Except when it doesn't. eg

* when the broadcaster screws up their RDS signal after a traffic report leaving you stranded on the wrong station.

* Or FM stations that run at different frequencies from different transmitters (this used to be a massive problem when driving long distances even just 20 years ago but now even the analogue car radios are digital devices that scan multiple frequencies to hop to the next frequency aired by a given station so you don't experience much cutout).

* Then there is the obvious issue of "dead zones" where the signals cannot reach (tunnels, some industrial locations, etc).

* Digital radio also suffers from frequent, albeit brief, cutouts while driving too but I've found that to have fewer dead zones than analogue.

* Bleeding used to be massive problem with analogue radio as well - this is another problem that was solved when radio started going digital.

So this is with 100 years of research and development into a protocol that requires an order of magnitude less bandwidth and yet most of the improvements have only been in the last 20 years when things like RDS (digital packets in analogue signals) and DAB have been introduced. Given that IP streaming video content isn't that far behind, just imagine how good it is going to be when that technology finally matures.

Re:How the BBC and ITV are fixing delays on World Cup live s... by 0xffff2 on Friday July 13, 2018 @06:31PM (#17527440)
> but now even the analogue car radios are digital devices that scan multiple frequencies to hop to the next frequency aired by a given station so you don't experience much cutout

Wait, is this really a common thing? How would I know if a car radio does this, because I'm 99% sure my car doesn't.

Re:How the BBC and ITV are fixing delays on World Cup live s... by AnssiH on Friday July 13, 2018 @10:20PM (#17528423)
The name of the feature is usually AF (RDS), all my car radios since 90s have supported it and all multi-transmitter FM stations here make use of it. I'm in Finland - no idea if it is less common in US.

https://en.wikipedia.org/wiki/Alternative_frequency

Re:How the BBC and ITV are fixing delays on World Cup live s... by laumars on Friday July 13, 2018 @07:07PM (#17527616)
Maybe it's not a thing any more? Or maybe it's not as clever as scanning multiple frequencies? I've not listened to analogue radio in the car for long distances in a while but I do remember there used to be a big problem with national radio spanning multiple different frequencies and your signal would drift out as you changed regions. This problem seemed to solve itself when RDS and "smart" radios started becoming a thing. However my experience is with video broadcasting rather than radio so I might have gotten some of the details wrong.
Re:How the BBC and ITV are fixing delays on World Cup live s... by mattacular on Friday July 13, 2018 @04:32PM (#17526435)
I love things that just work but it's a little unfair to compare radio technology that has been around for over 100 years and backed by huge public infrastructure investments with internet-based live streaming that has been around for (being generous) maybe 10-15 years at the most?
Re:How the BBC and ITV are fixing delays on World Cup live s... by reaperducer on Friday July 13, 2018 @05:03PM (#17526667)
maybe 10-15 years at the most

21 years ago, we learned to hate the word "Buffering..."

https://en.wikipedia.org/wiki/RealNetworks

Re:How the BBC and ITV are fixing delays on World Cup live s... by isostatic on Sunday July 15, 2018 @05:57AM (#17534564)
I remember an anecdote from an old school broadcast engineer I knew about 15 years ago. He recalled some sales guy from Real coming in and saying "with this new box we can broadcast to 5 thousand people". Engineer pointed to a picture of crystal palace transmitter that happened to be in the room -- "with that we can transmit to 5 million".

I'm not convinced how muliticast works to mobile devices, but it's a painfully edge case. This type of event occurs in the UK once every 4 years (the olympics doesn't pull in these numbers -- except for 2012 when it was hosted in London), and even then only when England do well (so once every 20 years)

That said, ITV latency seemed far shorter than BBC latency, watching ITV player seemed acceptable. Apart from the lackluster commentary and the adverts.

Re:How the BBC and ITV are fixing delays on World Cup live s... by vokep on Friday July 13, 2018 @04:55PM (#17526621)
Not really when theres a good chance its ending up going through radio technology still anyways (wifi).

And its a matter of complexity - its obvious why OTA would have less problems to solve in order to get the same performance and behavior of something more complex.

Re:How the BBC and ITV are fixing delays on World Cup live s... by laumars on Friday July 13, 2018 @05:06PM (#17526696)
OTA doesn't have less problems to solve. You have all the same problems of digital encoders etc (since all the media is digital anyway) PLUS the problems of transmission towers, solar events (I kid you not), wildlife, etc. You have the safety and cost problems supporting those hazardous and highly expensive equipment in remote locations.

IP streaming does actually solve a lot of problems. Plus these days OTA transmissions are all digital anyway. So serving that digital content via the internet is a natural progression. Sure things are superficially more complex at the moment but the technology hasn't matured yet.