Iptv

watty

IPTV would deliver on all the hype and more if we had this fibre

http://www.theregister.co.uk/2006/03/27/data_transmission_record/

running to the cabinet at the end of each street. Maybe we should get these guys to plan our MANs and BB infrastructure.

Of course without better regulation of Eircom and LLU no-one would be able to connect to it.

BrianD

Good old 'boffins' at work!

Am I correct in saying that this is what Magnet Networks are attempting to roll out. I am aware that they 'fibre-ed up' some new developments for this service but are relying on the incumbent network for the rest of us. They only offer BB in D6 anyway.

Also would you class iptv as 'internet broadcasting'? The reason I ask is that it seems to be excluded from regulation by the last broadcasting act.

watty

Internet Broacasting could be a stream from a bedroom web cam.

IPTV is using Internet to deliver real TV channels that already exist and hopefully at same quality as DTT, Cable and Satellite digital.

However DTT, Cable and Satellite can drive any number of set top boxes in your house for any number of TV sets with different channels at the same time with no performance/quality/cost penalty to the provider. (Unless he gives away the boxes, but that is once of cost).

IPTV can only to the SAME channel to each TV, unless you consume additional Broadband bandwidth for each channel.

Unless you use MPEG4 the bandwidth of one channel fairly kills adsl. MAgent use MPEg2 at lower bit rate so quality of their TV is poor compared to DTT, Satellite or cable.

Really you need 12Mbps to do Broadband and MPEG2 IPTV or 4 Mbps to do MPEG4 IPTV and BB.

HDTV makes problem worse for IPTV.

So BT for their IPTV adsl combine with a DTT (freeview) to have cake and eat it.

Cable TV can used shared Broadcast bandwidth for most channels and do one IPTV stream per user and BB if using DOCSIS2 or later (original Cable B not enough bandwidth).

Adsl on it own is on a loser here as BW for most people is too low and also it can't do the tricks of Cable TV. There is no DTT here, so they would have to pair with Satellite.

Things like Wireless Broadband can in theory to hybrid approach of Cable. Not limited like pure adsl is.

Another ploy is a hard drive (very big) and a only 100k bps always on download, then about 100 hrs of programing can be stored in advance on the hard disk and available for instant viewing or even differnt programs at same time on other screens in house via local LAN (100Mbps).

In theory a Satellite PVR (non-Sky) or a PC or dedicated box or an Xbox 360 or PS3 can be used to connect the network IPTV to a normal TV set.

watty

I wish I could write better

One of the first questions and preconceptions of those who are curious about IPTV is how similar it is to streaming video on the web, or 'Internet TV'. The answer is that the process of streaming the audio and video uses the same mechanism (RTP/RTSP), but the environment in which it is transported is strictly controlled by an ISP, never going onto the public internet. Being unicast at crappy resolution, streaming video on the web is abjectly awful and bottlenecked at every point – even the bravest of souls is tempted to commit hari-kari when the dreaded "Buffering…" appears on screen. No matter whether it's Real, Windows Media, Quicktime, Flash or anything else, it’s always dreadful. IPTV has a barrier to climb in the form of this particular preconception before anything else.

You can’t be watching TV and have your picture break up because someone else in the house has switched on their BitTorrent client and starting eating up all the bandwidth. Video signals over IP are extremely sensitive to jitter, packet loss, delay and many other conditions that exist in a normal network. This isn't such a problem when browsing web pages, or even for phone calls. People's tolerance of problems on their TV is very, very low in comparison to their PC. In fact, most even expect their computer to do something unpredictable and leave them totally confused (the infamous BSOD, or "Blue Screen Of Death"” being a prime example of this). The game isn't uptime of five nines, it's 100 per cent reliability. You don’t get to mess up even once.

Different types of TV signal from different broadcasters have differing bandwidth requirements. Most IPTV is now transmitted or encoded in an MPEG-4 codec variant (H.264 or Windows Media 9 typically) at the highest possible quality. For standard definition this means 1-4Mbit/s, and 6-10Mbit/s in high definition. If you're prehistoric and still using MPEG-2, the figures are 4-6Mbit/s and 25-30Mbit/s respectively. Encoding can be done using an average bitrate (ABR), but is handled efficiently by intelligently determining when additional information is needed in the stream – for example water, cartoons, sports and high action sequences require enormous detail and therefore more bandwidth. Scenes where there is little movement (e.g. talking head-style discussion or still shots) need hardly any bandwidth.

Maths geniuses will have worked out by now that trying to get TV down a phone line is a lot easier using MPEG-4 and high line speed DSL connectivity than using MPEG-2 and plain old vanilla DSL. It can be a real struggle when most people's lines aren’t close enough to their exchange to have enough space to reliably handle digital TV. Standard DSL, such as the new BT Max product, does 8Mbit max as ATM line speed and nearer to 7Mbit/s at the IP layer. You can fit a 1 standard definition video stream in it with very little room for much else. ADSL2+ can handle 3 SD/2 HD channels and VDSL2 many, many more at close range (and ADSL2+ rates elsewhere). Both have the limitation of distance, but greater bandwidth at the last mile is always beneficial. No one who has ever deployed this technology will ever tell you that the beer-mat maths actually work in the real world.

http://www.theregister.co.uk/2006/03/28/iptv_solving_home_wiring_problem/

I don't agree with all the conclusions, but the article explains well a lot of the issues and pitfalls. Deep pitfalls.

watty

Also what ever way you look at IPTV or connectivity in the home the stark reality is that maybe 30% of people can get aDSL and almost all the ADSL is too slow for IPTV on its own never mind BB as well as TV watching at the same time.

With no DTT and patchy cable/MMDS digital TV, if you are in an apartment it is time to look at hidden dishs or persuade the management company that you all want a communinal system.

And don't even think about VOD (video on demand).

The Wireless and Digital Cable operators are going to make Eircom's adsl efforsts look very silly, especially when TV is factored in as well as BB>

jwt

I think one thing that Joe Blogs forgets in all the hype is the one to many versus one to one bandwidth requirements.


For example SKY shoves out X Mbits of bandwidth which covers every square foot of Ireland and UK via the Sat.

To do the same thing individually to 1,000,000 people means you have to start chopping something’s or your trying to send 1,000,000 X

Easy stuff is that most houses will watch one maybe two channels at once so instead of beaming 400 channels you’re down to 2

Add in some behind the scenes caching, particularly if people use technology similar to SKY Planner. So say bookmark or schedule that I’m going to watch programme y tomorrow night after 9pm.

Throw in that while the kids are watching cartoons (nice low bandwidth stuff) you can watch a film.

But where I think the real technology will strike is when your PC predicts what you are going to watch and starts prefetching.

As an example, let’s say every evening I watch something on discovery channel about crimes. Now my PC goes off and looks at the guide software sees there are 4 possible 1 hour shows about crimes, police, forensics and unsolved mysteries.

So during the night while no TV is being watched it prefetches some if not all the content.

Similarly I watch action movies about retired Special Forces soldiers with a penchant for bows and arrows, or on a more likely note I watch every Jet Lee movie.

I think this is where the big advances are going to be in the near future.

My tuppence


John

watty

There is a box out already that records the last entire week of every TV channel on Freeview. You can browse and sit and watch anything at any time on any channel. Each day it replaces anything over a week old.

Sky will no doubt do this eventually too. Already on a 160G Sky+, 80G is reserved for future service.

Cartoons aren't low bandwidth.

Each house may have quite different viewing patterns, but any particular house watches mainly less than 10 channels.

None of the existing "prefetching" successful systems are PCs. It will be a box.

stereo_steve

I attended Cebit about two weeks ago and in the communications section everyone was talking about IPTV.

Alcatel had a lovely setup. They were showing off their high definition IPTV solution. For their system to function they were looking at 20Mb/s. What was particularily noticeable was their channel change time. It takes no more than 20ms to change a station!!! As soon as you request a channel, they increase the data rate to allow your decoder to buffer the video and start playing instantly. It was so impressive to see in action!

PICT0134.JPG

They also have nice features like chat. eg talk to people watching the same program as you.



Lucent seemed to focus more on low definition. Their system required 2Mb/s. I didn't find it half as impressive, which is understandable with a much lower bandwith. They seemed to focus alot on convergence. Phone, TV talking etc. They demonstrated recieving a phone call on the television, while the tv paused itself and used PVR technology to record what you missed.


I attended a couple of lectures here from Deutsch Telecom and they were talking about fibre to the cabinet and then using VDSL to get high data rates to the houses. The man giving the lecture said they believed 100MB/s is what they believe will be the data requirement for triple play with multi-room high definition television.

So what is eircom planning? While other telco's are planning high speeds are they just focusing on getting 2MB/s around the country? Which they can't manage! They really are a joke!!

Blaster99

eircom has done or is doing FTTC + VDSL trials from what I know. When they would roll it out probably depends on how NTL gets on.

zuma

Blaster99 wrote:

eircom has done or is doing FTTC + VDSL trials from what I know. When they would roll it out probably depends on how NTL gets on.

Honestly, have eircom ANY plans to do FTTH as VDSL will eventually run out of capacity....whereas Fibre directly to your computer...is well future proof for the next half century at least!

Has anyone got the foresight to impliment such a network and completely replace all the telephone lines with fibre?

cgarvey

zuma wrote:

Has anyone got the foresight to impliment such a network and completely replace all the telephone lines with fibre?

Has anyone got the money, more like. For something like that to happen, would mean an awful lot of "civils", as Smart call them! Let alone the labour intensive nature of the work.

cgarvey

watty wrote:

IPTV is using Internet to deliver real TV channels that already exist and hopefully at same quality as DTT, Cable and Satellite digital.

I'd love to see Magnet screengrabs/demo, but I can't imagine that it's worse than NTL Digital. Often I switch from BBC1 digital to analogue because of the compression artifacts. I have a very strong signal, and have had a few different boxes, and anecdotal evidence all suggest that it's not just me. Watching sport on Setanta is just painful. Presumably all at the expense of having the GOD channel and other such minority channels. Is Magnet really much worse?

Also, why are Magnet using MPEG2? Expense of the settops?

.cg

zuma

cgarvey wrote:

Has anyone got the money, more like. For something like that to happen, would mean an awful lot of "civils", as Smart call them! Let alone the labour intensive nature of the work.

How then are Verizon able to do it in areas of the US?

You have to start somewhere....lets say the more "affluent" areas of the cities downwards to large towns...etc....at least make a start.

bk

cgarvey wrote:

Is Magnet really much worse?

Yes, Magnet have to use ABR encoding which is about 4Mbps MPEG2, but NTL use statistical multiplexing allowing for Variable Bitrate encoding, allowing fast moving shows, etc. to increase to as much as 7 - 8 Mbps.

cgarvey wrote:

Also, why are Magnet using MPEG2? Expense of the settops?

I assume because MPEG4 is very new and the set top boxes for it are very expensive.

How then are Verizon able to do it in areas of the US?

Because Verizon is a very rich company ($101 Billion market cap) and it believes that this will be the way to dominate the triple play market far into the future. Also very importantly the US government has agreed that unlike DSL, Verizon doesn't have to open up it's Fibre network to it's competitors (LLU).

Eircom certainly doesn't have the money to do any of this. It will be a miracle if we get FTTC and VDSL.

watty

Chips for MPEG4 only really since this November 2005.

The set top boxes will soon be same price. Main increase in price is that HDD is more often standard for PVR and also the circuits to do Regular TV and HDTV etc.

NTL have a lot more bandwidth. Some wireless operators can likely have a service closer in quality and richness to Sky/NTL than Magnet who is limited by poor Eircom copper and ADSL2.

I have only personally seen Chorus Digital Cable and Chorus Digital MMDS, and its poorer than Satellite, but I have seen Sky even poorer due to misaligned dish (quality at 45% or so instead of 70% to 90%. I got about 80% quality on last minidish install, and it was a S/H slightly rusted one. We Electric wire brushed and threw some hammerite at it. Stuck it up while paint still wet).

I haven't seen NTL. But you can have a good signal level and poor quality causes increas in artifacts due to bad cable or interference.

bk

watty wrote:

Chips for MPEG4 only really since this November 2005.

I believe the issue is that the first generation MPEG4 boxes use general purpose DSP chips to do the work, while they do a great job, they are too expensive for a wide scale rollout, they are still waiting for cheaper dedicated chips to arrive.

watty wrote:

I have only personally seen Chorus Digital Cable and Chorus Digital MMDS, and its poorer than Satellite, but I have seen Sky even poorer due to misaligned dish (quality at 45% or so instead of 70% to 90%. I got about 80% quality on last minidish install, and it was a S/H slightly rusted one. We Electric wire brushed and threw some hammerite at it. Stuck it up while paint still wet).

I haven't seen NTL. But you can have a good signal level and poor quality causes increas in artifacts due to bad cable or interference.

Having seen all three, Sky is the best, NTL next, followed by Chorus. NTL is quiet close to Sky, I watch a lot of fast moving action shows (24, Battle Star Galactica) and sport on a 32" CRT, filtered through a TiVo and I've never noticed any pixelation problems, I find it to be very good quality.

cgarvey perhaps you have a big screen plasma or LCD?

cgarvey

Nope, I've seen at least 20 digital installs .. one on an LCD which was notably poorer, but the rest were all CRTs.. mine is a 32".. areas are D3, D1, D6, D12 and D24 .. all piss poor quality at peak time on the primary channels (RTE/BBC), and usually very poor on all other channels at all times. I'm picky, sure, but compared to Sky (varying quality from 60% upwards), NTL Digital is notably poorer. So it's not just my TV, or my install, and it's not just my high expectations. I don't know how widespread it is, but pixelation and settop box hanging seem to be pretty common, over on the IDCG fora/forums.

bk

cgarvey wrote:

I don't know how widespread it is, but pixelation and settop box hanging seem to be pretty common, over on the IDCG fora/forums.

My box use to hang frequently (very annoying as I use a PVR), but it seemed to stop a few months ago and hasn't happened since, so they seem to have improved that.

I've never noticed any pixelation, rock solid smooth picture. Maybe it is just better in my area (D9) or it just doesn't register with me.

Blaster99

cgarvey wrote:

Nope, I've seen at least 20 digital installs .. one on an LCD which was notably poorer, but the rest were all CRTs.. mine is a 32".. areas are D3, D1, D6, D12 and D24 .. all piss poor quality at peak time on the primary channels (RTE/BBC), and usually very poor on all other channels at all times. I'm picky, sure, but compared to Sky (varying quality from 60% upwards), NTL Digital is notably poorer. So it's not just my TV, or my install, and it's not just my high expectations. I don't know how widespread it is, but pixelation and settop box hanging seem to be pretty common, over on the IDCG fora/forums.

I would agree. NTL Digital looks massively compressed a lot of the time. I know people with boxes hanging too. Sky's picture quality is in a different league. I have about 80% SQ on Sky from what I recall.

watty

November was the dedicated chips.


Given Magnet & NTL bitrates, then Magnet has to be worse than NTL.

Of course on NTL if they use a Satellite feed they have recompression artifacts

Bitrates and quality and resolution vary tremondously from channel to channel on Satellite. But many "good" channels are indistinguishable from best DVDs on Satellite.

Quality is even more variable on NON-Sky platform varying from nearly unwatchable worse than a worn out VHS to perfect on some satellites, depending on resources, expertise and budget of broadcaster.