4oD

There's no bandwidth clog, VOD takes up the space of 1 video channel with a return path so you can tell the headend what you want to watch.

It replaced Front Row which was a Sky Box Office style service and took up much more bandwidth.

The programmes are totally VOD you can play, pause rewind, fast forward and programme on there.

I think there service is ideal.

Whereas TV is broadcast on the network to everyone, VOD is narrowcast to one particular user, it does not effect broadband users speeds.

Some may feel the free service is a gimmick but having access to over 500 films and hundreds of other programmes programmes using the same system is the plus side of it. The old Front Row service has now gone (freeing up over 50 TV channels frequencies ) and has been replaced with Teleport movies. If when I'm watching a film I stop watching I can pause it or fully stop it and return to watching live TV, it will remember where I got to and when I return can just play where I left it or go to the start and start it again.

Dam the need to go to the loo before pressing send...now 3 people have written what I was going to say!

As for the Channel 4 and BBC on demand stuff it would be ideal if they would let you access the Podcats and the stuff on the BBC Radio Player using VOD

I'm having a hard time following this one.

What you say would be true if cable consumers were receiving the broadcast signal in the same way as VOD, but they aren't -- it's broadcast, ie one copy of everything.

If you have 100,000 people, and 100 channels, by broadcasting the 100 channels you're using 100 units of bandwidth let's say.

If all 100,000 people decide they want to watch a different programme at the same time (or the same show skewed by 10 minutes) then you are using 100,000 units of bandwidth here.

With 100 broadcast channels it is easy to control quality of service. With an unpredictable number of people needing random information all at the same time, this becomes a nightmare.

Each individual user will be consuming less bandwidth on their particular wire, but that's not where the congestion is anyway -- it's at the server end.

Why do you think ISPs put limits on the amount of data each customer can download each month?

VOD isn't possible via satellite. Think of the bandwidth - there are over 6 million Sky subscribers, if every single one wanted to watch a VOD programme at the same time they'd need 6 million diffrent video channels. The nearest they can get is NVOD (near-video on demand) like Sky Box Office

The only way they could do it is via broadband..... which is probably why Sky have recently become an ISP!

But on a broadcast signal the data is shared anyway, there is no need to tell the headend and indeed it's not possible as there are multiple devices connected to each segment. Like I say there is no congestion on the client side, so any argument that VOD reduces client congestion is missing the point.



Perhaps because there are few people watching it. That's the problem -- VOD is not scaleable in the same way broadcast media is. If you have a free service, where the majority (rather than a small minority) of viewers are using it, the server-end congestion becomes immense compared with broadcast.

Yes, I said VOD is more efficient way of doing things than the traditional broadcast model or a PVR store and play system.

At the moment cable has VOD alongside the normal system, but it doesn't take up that much extra space. It would be far more efficient to scrap the broadcast system and have just a VOD/IP system like Homechoice.





Spread across all the cable headends and infrastructure, yes.
Coming down the wire into my flat, no - there's only 1 'unit of bandwidth'.

It's structurally no diffrent to that 100,000 people all downloading diffrent data using their cable internet connections. The only diffrence is that with VOD the STB is being used rather than a PC and the bandwidth of the programme is slightly larger

BTW, you can't watch something skewed by 10 minutes, the programmes get recorded of air and uploaded to the server sometime afterwards



That is true, but even with the broadcast channels it isn't that easy, you can't tell what level of service someone is getting at home from the headend, there's a lot of cable and electronics in between!

Got to agree with that - though of course it is handy if you happen to forget to tape something that just happens not to be repeated within the next week.

Also, you'd think rather than making the content available after the initial transmission they'd encourage people to watch the repeat editions first, rather than go straight to On Demand.


For other things though of course it would be useful - like a Film4 On Demand service - and also I see potential in the combination of interactive and On Demand services, so rather than things like the BBC News Headlines being shown in a three minute loop, you can watch them from start to finish.

Hardly slightly!!

ISPs rely on most users using very little bandwidth.

If every single Pipex account holder demanded 3Mbps, constantly, for 8 hours per day, the system would quickly collapse at the prices Pipex are charging -- and they're relatively expensive.

Added to this is the cost of supplying people in rural areas with service -- not a trivial matter with broadband, and essential if you do away with the broadband systems!

At the end of the day, VOD only works if there is an effective way of choking the numbers of people demanding the service at any one time. Pay TV is ideal, because you can easily factor in the cost of the data transfer. I'm sure that for pay-TV, particularly minority interest pay-TV/PPV, VOD is much more efficient than broadcast.

Free TV is an entirely different model. People want lots of access, and not have to pay per programme. In this model, VOD is utterly unsuitable.

But that was my point - sending everything to everyone and having a PVR recording it all is a far less efficent and elegant system than just sending what people want, when they want it.

I don't really care how congested the cable companies equipment is, that's not the point. The real pinch point when it comes to broadcasting is the bandwidth from broadcaster to customer. Imagine if cable turned completely VOD and the fat pipe bringing me 200 Tv channels only brought me 1 at a time (like Homechoice do) imagine what else could be done with all that other bandwidth - I could have one heck of a net connection for a start!

In terms of the headend it's essentially the same as having all their subscribers getting their own net connections. The quantities of bandwidth are larger, but not un-doable with the right technolgy

So, now that we've decided that it doesn't matter how fat NTL's pipe has to be to cope with all this stuff, we're now saying that we should use the broadcast pipe for more data transfer?

What you have to bear in mind is that, by definition, that fat pipe coming into your house is shared with countless other individuals -- it's not just for you. The infrastructure resembles a bus rather than a star formation when it comes to network traffic -- and you can't send more than x Mbps through that bus.

So while that fat pipe might have say 400Mbps bandwidth, there are perhaps 2,000 people sharing it. 200Kbps is hardly worth getting worried about. And it's unidirectional, so to make it work in both directions you'd have to run it in half-duplex, slowing it down still further. And that's before we even begin to think about all the data collisions from having an effective 10-mile ethernet connection with 2000 hosts.

And lets assume for a minute that everyone did have 400Mbps into NTL. They'd have to have an internet pipe to end all internet pipes to cope with the potential data rate.

All this may be inconsequential, but it's all cost that gets sent back to the customer.

Oh I don't care, I just want this free stuff...which I can't get at the moment. Dumbass NTL.

Was my video handy for anyone?