Wimax?

bk

useruser wrote:

OK, it's perhaps not quite as good as sat or cable but so what? If it's priced right and included with my voice and broadband package that's fine by me. I am that user who is happy with the basic NTL analogue service - I just don't watch that much TV.

It is far inferior to both cable and sat.

Also why do you think IPTV would be cheaper then cable or sat? The costs for IPTV equipment are more expensive then either cable or sat.

For example, NTL's packages of TV + BB + Blueface VoIP is far cheaper then the triple play package including IPTV from magnet.

Care to explain?

useruser wrote:

This is just silly, who's talking about overcoming physics? Shannon's law still has plenty to give! If we had been discussing this 15 years ago would you have been telling me that DSL was impossible?

Unshielded Twisted Pair cable gives you about 1MHz, Shield Coax gives you about 860MHz, potentially more.

DSL technology is older then 20 years. It was a very well understood technology for a long time, there isn't anything magical about it. It was just that the telephone companies didn't want to invest in it as it would savage their per minute dial-up charges.

The limits of UTP are well understood, no one is going to come along and magically make it faster.

useruser wrote:

Both Neuf and Free use DSL for the vast majority of their subscribers - it is absolutely possible to do this. I notice also that PCCW is leading research into HDTV over DSL - I assume you would counsel them to save their money?

Nope, since there network is mostly fibre, they will be able to make good use HD.

useruser wrote:

So, at least you'll give me VDSL then! We're getting somewhere.

Do you not understand what VDSL means? VDSL means you will only get high speeds at a distance of up to 1 mile from the exchange. You need to run fibre right to the curb (your local estate) in order to make VDSL work. IPTV will definitely work over VDSL, I never said it wouldn't, I said good quality IPTV wouldn't work over standard DSL (ADSL, ADSL2+), VDSL has plenty of bandwidth to make IPTV work, but Eircom would need to spend billions to roll out VDSL, don't hold your breath.

useruser wrote:

http://www.theregister.co.uk/2005/09/28/bt_iptv/ BT to launch IPTV by summer 2006, VoD included apparently, they claim that the viewer will be able to switch between freeview and BB channels on the same box. Sounds to me like they are going to do IPTV over DSL - what's your read on it? (Don't just say that it's not possible!)

Oh, I'm well aware of this project. What BT are hoping is that 95% of the time people will watch TV via freeview. Only for the other 5% of the time will people use IPTV or VoD. There are also hoping that two people in the house won't use the IPTV stream at the same time. They will probably also build a PVR into the box to locally cache some popular content (new release movies, most popular shows, etc.) in order to reduce the use of IPTV.

In this setup IPTV is really only there to order the odd pay per view movie, not for normal TV viewing. They are doing all of this to patch over the problems with IPTV and it actually proves my point. If IPTV was so great, then BT wouldn't bother with freeview and would deliver all the TV channels via IPTV. BT's solution is actually quiet a clever work around.

useruser

bk wrote:

It is far inferior to both cable and sat.
Also why do you think IPTV would be cheaper then cable or sat? The costs for IPTV equipment are more expensive then either cable or sat.
For example, NTL's packages of TV + BB + Blueface VoIP is far cheaper then the triple play package including IPTV from magnet.

You are being silly again bk - IPTV is the only option if all you have is a copper loop, do you not think that's going to be cheaper than running new cable? If an operator is introducing a competing product chances are they are going to undercut the incumbent. Magnet seem to be a monopoly where they are offering TV - through deals with developers. I'm not really surprised they are expensive.

Unshielded Twisted Pair cable gives you about 1MHz, Shield Coax gives you about 860MHz, potentially more.
DSL technology is older then 20 years. It was a very well understood technology for a long time, there isn't anything magical about it. It was just that the telephone companies didn't want to invest in it as it would savage their per minute dial-up charges.
The limits of UTP are well understood, no one is going to come along and magically make it faster.

Care to guess what the maximum speeds we will see out of UTP will be in 10 years? Your view is simplistic, DSL was very expensive to do 20 years ago, the chips are now dirt cheap. Maximum loop lengths and data rates have increased every year for the last 20 years, are you saying that they will go no further? Hint: Cioffi has predicted 1Gb DSL will be a possibility within 10 years.

Nope, since there network is mostly fibre, they will be able to make good use HD.

HD over DSL research, not fibre - re-read the point.

Do you not understand what VDSL means? VDSL means you will only get high speeds at a distance of up to 1 mile from the exchange. You need to run fibre right to the curb (your local estate) in order to make VDSL work. IPTV will definitely work over VDSL, I never said it wouldn't,

Sense of humour failure? I am well aware of what VDSL is and is not, thanks for that bit of patronising.

I said good quality IPTV wouldn't work over standard DSL (ADSL, ADSL2+), VDSL has plenty of bandwidth to make IPTV work, but Eircom would need to spend billions to roll out VDSL, don't hold your breath.

So, now we're down to "good quality" IPTV being impossible over ADSL2+, this is getting stupid - not only is it possible, it is being done.
Give me some qualitative problems with SDTV over DSL, I couldn't see any when I was looking at it.

Oh, I'm well aware of this project. What BT are hoping is that 95% of the time people will watch TV via freeview. Only for the other 5% of the time will people use IPTV or VoD. There are also hoping that two people in the house won't use the IPTV stream at the same time. They will probably also build a PVR into the box to locally cache some popular content (new release movies, most popular shows, etc.) in order to reduce the use of IPTV.

In this setup IPTV is really only there to order the odd pay per view movie, not for normal TV viewing. They are doing all of this to patch over the problems with IPTV and it actually proves my point. If IPTV was so great, then BT wouldn't bother with freeview and would deliver all the TV channels via IPTV. BT's solution is actually quiet a clever work around.

[/QUOTE]

Do you think BT shouldn't bother with IPTV at all then? I assume you think this service is going to be a flop? Perhaps they chose to do it this way for licencing reasons too? Your notions are laughable - BT is apparently "hoping" that it's users won't use a service that they are about to launch!

Assuming that they will be using IPTV for VoD, why on earth would they want to reduce it's use? Are you stating that the service will not work for VoD?

useruser

bk wrote:

2x14MHz is 1.4GBit/s worth of bandwidth. I suppose they will try to deliver IPTV down this bandwidth.

What? How did you come up with that figure? Explain please.

bk

useruser wrote:

What? How did you come up with that figure? Explain please.

I deleted that post 5 minutes after I posted it, I don't know what I was thinking, to long of a day.

It is actually, about 150Mbit/s. 1MHz gives you about 5Mbit/s with all the error checking for wireless.

useruser

bk wrote:

I deleted that post 5 minutes after I posted it, I don't know what I was thinking, to long of a day.

It is actually, about 150Mbit/s. 1MHz gives you about 5Mbit/s with all the error checking for wireless.

What FWA product gives you 150mb in 2x14MHz?

bk

useruser wrote:

You are being silly again bk - IPTV is the only option if all you have is a copper loop, do you not think that's going to be cheaper than running new cable? If an operator is introducing a competing product chances are they are going to undercut the incumbent. Magnet seem to be a monopoly where they are offering TV - through deals with developers. I'm not really surprised they are expensive.

Very rarely is UTP the only option. By law it is required that you can receive free TV via aerial. Sat is available to everyone except in apartments. However apartments are usually also serviced by cable and DTT.

Magnet are only a monopoly in the areas where they have FTTH (which IPTV can work well on). They don't have any monopoly in DSL areas, as they can be serviced by sat, cable and in the future DTT.

Look ok, here are the facts:

Q: Can you do one SD channel over ADSL/ADSL2+

A: Yes

Q: Will the picture and sound quality be good as cable, sat or fibre.

A: No

Q: Why

A: Because the bandwidth limitations of DSL they will have to use a lower bit rate, causing lower quality, higher artefacts and more breakup.

Q: Can you do 2 SD streams on ADSL/ADSL2+

A: Yes, for only about 50% of the customers (close to the exchange) and the PQ and SQ will suffer even further and reduce the amount of bandwidth available for the BB and VoIP.

Q: Why?

A: Bandwidth limitations of the tech.

Q: Can you do 3 SD streams on ADSL/ADSL2+

A: No

Q: Will you be able to do 1 HD stream on ADSL/ADSL2+

A: Yes, for about 25% of the customers (very close to the exchange).

Q: Will you be able to do 2 HD stream on ADSL/ADSL2+

A: No

Q: Can you do multiple SD and HD streams with VDSL?

A: Yes

Q: Well then isn't IPTV over VDSL great?

A: Yes, but it will require running fibre to within a mile of everyones home, building curb side exchanges with mini dslams. Such a rollout would cost billions and would only give you a service equivalent to what is already available on cable.

Q: Is there any other way?

A: Yes you could bond two or three UTP cables together and run ADSL2+ across them to give you more bandwidth.

Q: Wouldn't that work great?

A: Yes, but again it would require digging up everyones road and laying lots of copper, again it would cost billions. If you were going to do that, then you might as well lay fibre or coax.

Q: Why would you do that?

A: Because 70% of the cost is labour and road digging licenses. There isn't much difference in the cost of the materials.

Q: Will some magical elf come along and develop some new technology in the next 10 years and make more crap quality Eircom line attached to the exchange 5 miles away suddenly go faster?

A: No, ADSL2+ is it. All the technologies being developed now involve running fibre very close to your home and then doing the last few hundred metres using the existing copper. Any such fibre rollout will cost billions. Don't hold your breath for Eircom to do this or any other company.

Q: Will IPTV be cheaper then cable or sat.

A: No

Q: Why?

A: IPTV infrastructure and tech is far more expensive then sat and it quiet a bit more expensive then cable (but not as a big gap to sat).

Q: Will there be a niche market for IPTV over ADSL2+?

A: Yes of course

Q: Will it ever really challenge fibre, cable, sat or DTT?

A: No

Those are the facts, end of story.

bk

useruser wrote:

What FWA product gives you 150mb in 2x14MHz?

It is shared amongst all the users on the sector.

useruser

bk wrote:

Very rarely is UTP the only option. By law it is required that you can receive free TV via aerial. Sat is available to everyone except in apartments. However apartments are usually also serviced by cable and DTT.

You missed the point again bk! UTP is the only reasonable option available to most telcos.

Magnet are only a monopoly in the areas where they have FTTH (which IPTV can work well on). They don't have any monopoly in DSL areas, as they can be serviced by sat, cable and in the future DTT.

And as far as I know they don't offer TV outside of the FTTH areas?

Look ok, here are the facts:

[.. lots of Qs and As ..]

Those are the facts, end of story.

So, finally you agree with me - IPTV over DSL is a viable product - I disagree that it is niche as it has too many big players behind it and already is proven in competitive markets. You prefer cable and sat but most telcos don't have access to those - you seem to be suggesting that they should just give up on the notion altogether.

Interesting claim that DSL capacity and reach will not increase significantly - what's that based on?

Now, tell me - what FWA product can do 150mb in 14MHz? (I think I know the answer to that one already.) - Just saw your followup, what do you mean "it's shared"? Name a FWA product that can do 150mb in that little spectrum.

bk

useruser wrote:

You missed the point again bk! UTP is the only reasonable option available to most telcos.

Yes, but not for customers, they don't carry how they get the TV, they just want it to meet their needs and be good quality.

useruser wrote:

And as far as I know they don't offer TV outside of the FTTH areas?

They do, there are many reports of people here on boards who have gotten it and the reports so far aren't good. Go do a search and read them for yourself.

useruser wrote:

So, finally you agree with me - IPTV over DSL is a viable product - I disagree that it is niche as it has too many big players behind it and already is proven in competitive markets. You prefer cable and sat but most telcos don't have access to those - you seem to be suggesting that they should just give up on the notion altogether.

I'm saying unless the telco is willing to invest a lot of money in rolling out fibre to within a mile of your home, it isn't worth doing.

It is important to note that all the telcos that are doing IPTV in the US will be using either FTTH or are running Fibre to The Curb within 1 mile of the house and then using VDSL.

useruser wrote:

Interesting claim that DSL capacity and reach will not increase significantly - what's that based on?

Please see this graph for the reality faced by ADSL2+:
http://www.internode.on.net/adsl2/graph/

useruser wrote:

Now, tell me - what FWA product can do 150mb in 14MHz? (I think I know the answer to that one already.) - Just saw your followup, what do you mean "it's shared"? Name a FWA product that can do 150mb in that little spectrum.

150MBit/s in 28MHz not 14 and I mean that the bandwidth is shared by all the users connected to the particular sector on the transmitter.

useruser

bk wrote:

Yes, but not for customers, they don't carry how they get the TV, they just want it to meet their needs and be good quality.

Neuf? Free? both doing ADSL2+ to the vast majority of their customers.

They do, there are many reports of people here on boards who have gotten it and the reports so far aren't good. Go do a search and read them for yourself.

I'll see if I can find any of these reports - don't happen to have a link do you?

I'm saying unless the telco is willing to invest a lot of money in rolling out fibre to within a mile of your home, it isn't worth doing.

And BT and numerous other telcos disagree with you.

It is important to note that all the telcos that are doing IPTV in the US will be using either FTTH or are running Fibre to The Curb within 1 mile of the house and then using VDSL.

Not true, SBC are not running fibre.

Please see this graph for the reality faced by ADSL2+:
http://www.internode.on.net/adsl2/graph/

This shows loop lengths TODAY - are you saying that these cannot increase for some physical reason?

150MBit/s in 28MHz not 14 and I mean that the bandwidth is shared by all the users connected to the particular sector on the transmitter.

[/QUOTE]

More nonsense, let me rephrase the question - what FDD FWA product can do 150mb (I said 2x14Mhz, not 28MHz). Come to think of it, 28MHz isn't enough for any TDD system to do it either - care to name a FWA product in either scenario?

bk

useruser wrote:

I'll see if I can find any of these reports - don't happen to have a link do you?

Just a few I quickly found:

http://www.boards.ie/vbulletin/showpost.php?p=50940770&postcount=30
http://www.boards.ie/vbulletin/showpost.php?p=3235589&postcount=3
http://www.boards.ie/vbulletin/showpost.php?p=50986409&postcount=5

useruser wrote:

Not true, SBC are not running fibre.

BBR: How about SBC's "Project Lightspeed"? Our understanding is that SBC was testing an ADSL2+/VDSL hybrid, but was unhappy with the results; they should should soon announce the use of VDSL2 for their next-gen network and U-Verse IPTV services, correct?

DB: SBC is selling satellite to 50% of their users -a fancy TIVO style set top and a slow DSL connection, and upgrading the rest to low profile VDSL2 they call fiber to the node. From the projected 2,000-5,000 feet, low profile VDSL2 is maybe 20 meg down, 1-3 meg up, most of which will be used for their video. They've slipped a year, with 2008 now the goal for 18 million homes completed out of their 30 something million home target. Also called "fiber to the press release" (it's really DSL) and "fiber to the rich" (they are only building the "high-value" customers). Investment is less than 30% of what Verizon plans.

SBC are doing Fibre To The Neighbourhood (under 1 mile) and then VDSL2. So it is mostly an expensive fibre rollout.
Note even with FTTN and VDSL2 they are still only getting 20Mbit/s, which isn't enough for two HD streams.

Bellsouth were going with bonded ADSL2+, but since they got bought by Verizon, that will be dropped for FTTH.

useruser wrote:

This shows loop lengths TODAY - are you saying that these cannot increase for some physical reason?

Yes, the limits of the physical characteristics of the medium. The further you go the more noise you need to deal with, there isn't any magical pixie dust that will fix this problem.

Think of it this way, ADSL is over 10 years old, ADSL2+ is new, in that 10 year period, they haven't been able to increase the speed for distances beyond 3.5k. This is because it simply isn't possible. The further you go, the more information you lose to noise interference, the error correction codecs can only deal with a certain amount of data lose.

In fact the difference between ADSL and ADSL2+ is that ADSL uses up to 1.1MHz of spectrum and ADSL2+ can use up to 2.2MHz. However 2.2MHz of spectrum simply isn't available beyond 3.5km due to noise interference, so ADSL2+ and ADSL are exactly the same at distances beyond 3.5km.

There is also nothing magical or new about VDSL2+, it is just a version of DSL specially tuned to perform well at very short distances, rather then over long distances.

All DSL (along with Wifi, Digital Radio and TV, cable, cordless phones, etc.) use something called Orthogonal frequency-division multiplexing or OFDM to encode the digital data for transmission and it includes the error correction. OFDM is not magical or new, the maths for this was first done back in 1957.

The limits of OFDM are easily understood and modelled and there is no magical new technology that will come along and change it.

You can read about it here:
http://en.wikipedia.org/wiki/COFDM

useruser wrote:

More nonsense, let me rephrase the question - what FDD FWA product can do 150mb (I said 2x14Mhz, not 28MHz). Come to think of it, 28MHz isn't enough for any TDD system to do it either - care to name a FWA product in either scenario?

Actually Digiweb have 2 slabs of 25MHz frequency in the 3.5MHz range, giving them a total of 50MHz. They also have another 56MHz in the 10.5GHz range.

AFAIK Digiweb are using Airspan pre-wimax kit.

The important thing to figure out is how much bandwidth you can get per MHz. With DSL is is about 8Mbit/s for 1MHz of spectrum. With wireless they will need to use more error correction and lower modulation to overcome lost data, but they should be able to get about 2 - 4 MBit/s per 1MHz.

So 2MBit/s X 50MHz = 100Mbit/s

Of course this is shared. How else did you think Digiweb were able to offer up to 9MBit/s products?

useruser

bk wrote:

Just a few I quickly found:

http://www.boards.ie/vbulletin/showpost.php?p=50940770&postcount=30
http://www.boards.ie/vbulletin/showpost.php?p=3235589&postcount=3
http://www.boards.ie/vbulletin/showpost.php?p=50986409&postcount=5

Excellent, another working IPTV deployment over DSL - the first quote had problems initially but is now working. The second is fibre and the third is working fine (and it seems to be with 2 TVs?) Not doing your argument any favours bk - thanks for the links.

SBC are doing Fibre To The Neighbourhood (under 1 mile) and then VDSL2. So it is mostly an expensive fibre rollout.
Note even with FTTN and VDSL2 they are still only getting 20Mbit/s, which isn't enough for two HD streams.

They are also using ADSL2+ without FTTC - read up on them again, obviously their market is huge so they will use whatever makes sense.

Yes, the limits of the physical characteristics of the medium. The further you go the more noise you need to deal with, there isn't any magical pixie dust that will fix this problem.

This is disingenuous, DSL has continued to increase in speed and reach every year for the last 10 years.

Think of it this way, ADSL is over 10 years old, ADSL2+ is new, in that 10 year period, they haven't been able to increase the speed for distances beyond 3.5k. This is because it simply isn't possible. The further you go, the more information you lose to noise interference, the error correction codecs can only deal with a certain amount of data lose.

What? What proportion of loops are beyond 3.5km? Rubbish again bk, of course speeds & reach have increased.

Actually Digiweb have 2 slabs of 25MHz frequency in the 3.5MHz range, giving them a total of 50MHz. They also have another 56MHz in the 10.5GHz range.
AFAIK Digiweb are using Airspan pre-wimax kit.
The important thing to figure out is how much bandwidth you can get per MHz. With DSL is is about 8Mbit/s for 1MHz of spectrum. With wireless they will need to use more error correction and lower modulation to overcome lost data, but they should be able to get about 2 - 4 MBit/s per 1MHz.

So 2MBit/s X 50MHz = 100Mbit/s

Haha! You added together their 3.5GHz and 10.5GHz spectrum! Why not add in some 5.8GHz, 2.4GHz and make it look really impressive? I'm sure you could easily get up to 1.4Gb. Pure drivel bk, you don't know what you're talking about here.

Of course this is shared. How else did you think Digiweb were able to offer up to 9MBit/s products?

So, their broadcast WLL gear can do ~10mb (lets be generous) to a sector (perhaps in 2x3.5MHz?), not much room for TV I would have thought - will they have a limit on the number of channels that can be watched simultaneously on a sector?

watty

This is a pointless arguement.

I agree, useruser that IPTV and conventional VOIP can be made to "work" within a limited definition of "work".

In the medium to long term straight IPTV only, will only be used by people that due to monopoly situations can get nothing else. The successful IPTV/VOD in medium to long term will ALL be hybrid mix of broadcast DVB + background always on transfer to a local hard disk.

An always on 100K can deliver 40 extra DVD quality films using broadcast (still only 100k to 10,000 users) "IP" transfer per month to a local disk. Similar quality "live" IPTV in Magnet sense needs about 6Mbps on top of BB used for Skype , browsing, downloads etc for ONE viewer/channel.

Satellite DVB can deliver total bandwidth 30Gbps on one dish. Terrestrial DVB can deliver 300Mbps on one aerial, cable DVB about 1 or 2 Gbps total.

BT have been very smart on their IPTV. And will get smarter. They are/will be doing as I suggest. It won't be Magnet style IPTV at all, mostly DVB-t and background downloads.

Most of what Bk says is perfectly correct and useruser seems determined not to see the big picture.

Yes adsl telco would like to take market from Cable TV and Satellite TV, but the way the most of them are approaching TV isn't going to do it except in apartments where they have a monopoly.

The two problems they have is they don't have broadcast bandwidth of Satellite or Cable or Terrestrial for broadcast TV and the model they are using to deliver TV as individual TV IP streams is doomed.

Telco cable does have potentially higher per person Broadband IP data speed than Cable or Wireless, as cable the bandwidth is shared between many users (which is why DVB works well). For adsl the bandwidth isn't shared at all, so there is no advantage to Broadcast. All the bandwidth is per person.

That is why BT is smarter than Magnet. By adding Freeview (DVBt) AND adsl in the same box they now have 1/3rd the broadcast bandwidth of cable (instead of ZERO on ADSL) and somewhat more per person bandwidth than DOCSIS. The final part of BT's box to success will be a 400G or 1Terabyte HD in ther box. I'll bet that will be the case with 18months if not already.

If I was mod, I'd close this thread as BK and useruser are starting to bit each other's tails.

bk

watty wrote:

If I was mod, I'd close this thread as BK and useruser are starting to bit each other's tails.

Please do. I'm finished anyway.

Blaster99

Ah come on, it's entertaining.

crawler

Has me laughing anyway

(been away for a bit...hello all)

watty

Maybe useruser works for a copper twisted pair type Telco?

Welcome back to Sunny no Snowy no Sunny... Boards.ie

crawler

Maybe watty should educate people on how to use spectrum properly - i.e. frequency resuse, vertical and horizontal polarisation, 30 degree sectors, down and up tilt etc....you can resuse 28Mhz X 2 a hell of a number of times on the same base

Sigh....I despair....

Probably being unfair....pre paddy's day blue I think....or I miss Germany...who knows...!

useruser

Ah, once more onto the fray. Call me the IPTV apologist!

watty wrote:

This is a pointless arguement.

I agree, useruser that IPTV and conventional VOIP can be made to "work" within a limited definition of "work".

I'll live with that Watty, my argument is simply this:

IPTV over DSL exists, is proven and is in very active development by many, many telcos worldwide who realise that they are going to lose revenue to other operators unless they step up to the mark.

I accept that it has its limitations and that cable and satellite can provide a better user experience today (multiple simultaneous streams, HD and possibly some SD qualitative differences).

I think it is foolish to bet against it in the long term. I expect the TV experience to be entirely VoD at some point (with the exception of the news of course ;-) This is a step towards that, obviously this is not realistic today.
I think your "fake VoD" solution (not intending to be disparaging here) is a medium-term solution, clever as it is I expect to see that intelligence move back into the network. Note that I am not claiming that IPTV will become dominant!

[.. interesting points, the 100kbps figure is food for thought ..]

Most of what Bk says is perfectly correct and useruser seems determined not to see the big picture.

I think bk is the blinkered one - he/she can't see that there is a new, tested and proven TV delivery method out there. It's gaining market share already and has massive investment behind it. To say that it won't succeed because it's just not as good is the old beta vs vhs debate.

Yes adsl telco would like to take market from Cable TV and Satellite TV, but the way the most of them are approaching TV isn't going to do it except in apartments where they have a monopoly.

And yet, year after year the number of such subscribers increases - I have no axe to grind one way or the other - I just see a working alternative to the TV incumbents.

The two problems they have is they don't have broadcast bandwidth of Satellite or Cable or Terrestrial for broadcast TV and the model they are using to deliver TV as individual TV IP streams is doomed.

It's doing surprisingly well for a "doomed" technology!

If I was mod, I'd close this thread as BK and useruser are starting to bit each other's tails.

God forbid, he hasn't told us how he came up with the 1.4Gb figure yet - there's a nobel prize in that at least!

(just kidding bk!)

edit: grammar what is wrong & bad speling

useruser

crawler wrote:

Maybe watty should educate people on how to use spectrum properly - i.e. frequency resuse, vertical and horizontal polarisation, 30 degree sectors, down and up tilt etc....you can resuse 28Mhz X 2 a hell of a number of times on the same base
Sigh....I despair....
Probably being unfair....pre paddy's day blue I think....or I miss Germany...who knows...!

Hi crawler,

What's your point? I think everyone realises that frequency can be re-used with V/H pol and that tilt helps with an overall frequency plan but how does either affect the capacity a sector can deliver to individual users?

useruser

useruser wrote:

I thought that, am I correct in thinking the 3.5GHz licences do not permit TV? How will Digiweb get around that?

Can you write some more about how you think Digiweb will do TV over Metro (is that an Airspan product?) I understand it's a DOCSIS system but where will they get the bandwidth from? 2x14MHz just isn't very much spectrum - what am I missing?

Watty - this got lost in the rants, can you tell us more?

watty

The licences are probabily someplace on www.comreg.ie

I can't tell you more.

OT a bit
Believe it or not DVB-h on 5MHz allows 11Mbits/s after error correction. They suggest 22 x 500kbps MPEG4 TV channels. I'd guess sort of PSP / mobile phone kind of resolution, not regular TV size resolution. It would equate to one full quality HDTV MPEG4 though, showing how impressive video compression is compared with Audio. (Digital phone Audio quality (VOIP) needs about the same BW as analog audio!)

useruser

watty wrote:

The licences are probabily someplace on www.comreg.ie

I can't tell you more.

I'm guessing from your previous posts that they will do this "fake VoD" you were talking about (background transfer to offline storage). I'm also guessing that they won't be able to provide a full TV service? Sounds interesting though, must admit I would like this service, particularly if it were possible to order movies from a very large selection (maybe "booking" them for transfer over the next day or so.)

OT a bit
Believe it or not DVB-h on 5MHz allows 11Mbits/s after error correction. They suggest 22 x 500kbps MPEG4 TV channels. I'd guess sort of PSP / mobile phone kind of resolution, not regular TV size resolution. It would equate to one full quality HDTV MPEG4 though, showing how impressive video compression is compared with Audio. (Digital phone Audio quality (VOIP) needs about the same BW as analog audio!)

VoIP bandwidth requirements are so low that it's not really worth paying for the extra CPU to lower it much further (Toll quality G711 at 20ms is ~110kbps, G729a @40ms is ~28kbps (including IP overhead)).

Blaster99

Digiweb's PR at the time mentioned TV. Mind you, it mentioned a telephone service as well and that didn't seem to work out.

watty

My Digiweb phone is fine on incomming calls, but a bit poor on outgoing. There is supposed to be some kind of firmware upgrade soon to fix this. Perhaps we will hear more about the TV after the phone bugs are ironed out.

They could do one IPTV channel but some kind of box that connects to coax feeding the Modem/POTS ports would be more useful and might allow shared bandwidth. Just guessing.

Blaster99

You could never do point-to-point IPTV with wireless, there's not enough bandwidth in the sector. They would have to broadcast the entire channel set, like on cable. It seems useruser's point is that there's not enough bandwidth for that either and assuming that's correct, it's all a bit puzzling. I guess the way to do it is to buy some spectrum that's dedicated to TV and then broadcast away.

useruser

watty wrote:

They could do one IPTV channel but some kind of box that connects to coax feeding the Modem/POTS ports would be more useful and might allow shared bandwidth. Just guessing.

I don't understand what you mean by "coax feeding the POTS ports" Watty?

useruser

Blaster99 wrote:

You could never do point-to-point IPTV with wireless, there's not enough bandwidth in the sector. They would have to broadcast the entire channel set, like on cable. It seems useruser's point is that there's not enough bandwidth for that either and assuming that's correct, it's all a bit puzzling. I guess the way to do it is to buy some spectrum that's dedicated to TV and then broadcast away.

Agreed, I can't see how they can do it - even assuming they don't go down the inefficient IPTV route there isn't sufficient bandwidth available. I imagine they are using 2x3.5MHz channels for FWA - how can there be enough room for TV as well as broadband?

Did they explicitly say that they were going to use their Metro product? Does Metro encompass a range of technologies or is it just the Airspan Wimax product? If they are having difficulty getting VoIP to work OK on Metro what chance have they with TV?

As far as I'm aware they haven't got any licences outside of 3.5 and 10.5, 3.5 doesn't have the bandwidth, 10.5 CPE is way too expensive. Who knows, maybe they are going to do IPTV over DSL! I'm stumped - answers please!

watty

Metro offers up to 6M at 10:1 for BB.
http://www.digiweb.ie/broadband_metro_services.asp?i=80&i2=81&i6=91&zzz=hm

I'd say that is enough to allow at least one IPTV MPEG4 channel and Broadband at Magnet quality BB/TV. But I don't think that is how it will work. But I'm only guessing.

The Metro system uses a box to convert from 10GHz microwave to essentially Cable TV on a coax. At the moment it only has DOCSIS on it to a Digital Cable TV type modem. The same coax could possibly have a set-top/pvr type box to feed a TV set, using any mix of per user IP traffic and shared broadcast bandwidth. Obviously broadcast datastream can be the same bandwidth for all users on the sector, just as it is for all users on a cable TV segment.

It isn't wimax. There is enough BW for TV as well as BB on the 10GHz. I'm not sure of the 3.6Ghz spec, it will be on comreg site someplace.

Wimax is a good design, but mainly a method of selling Intel chips.

Phones have been working on DOCSIS / Digital cable for 10 years, AFAIK the phone issue is just a teething bug with the conversion process.

POTS= Plain Old Telephone System ports (two) on the Thomson DOCSIS (digital cable TV) modem.

Metro is kind of NTL by wireless, not Wimax.

RF Parameters
Downstream
Frequency		Power	-3 dBmV
Signal to Noise Ratio	29 dB	Modulation	QAM64

Upstream
Frequency		Power	40 dBmV
Upstream Data Rate	5120 Ksym/sec	Modulation	QPSK

Notice downstream is QAM64. This means roughly 8M bits for each 1MHz. So sector download for 28MHz is 224Mbps before error correction overhead. Upstream is 5M SYMBOLS/s and QPSK = 2 bits per symbol = 10 Mbps before error correction.

A normal resolution channel in MPEG4 is 1Mbps to 3Mbps depending on quality. HDTV/MPEG4 is about 5Mbps to 12Mbps depending on quality. Asssuming half the sector BW was used for broadcast data stream, then 10 HDTV channels are possible. It may also be that more than 28MHz is available for downstream.

useruser

watty wrote:

Metro offers up to 6M at 10:1 for BB.
http://www.digiweb.ie/broadband_metro_services.asp?i=80&i2=81&i6=91&zzz=hm
I'd say that is enough to allow at least one IPTV MPEG4 channel and Broadband at Magnet quality BB/TV. But I don't think that is how it will work. But I'm only guessing.

Their 6mb product is €300/month so I'm guessing it's not aimed at home users.

The Metro system uses a box to convert from 10GHz microwave to essentially Cable TV on a coax. At the moment it only has DOCSIS on it to a Digital Cable TV type modem. The same coax could possibly have a set-top/pvr type box to feed a TV set, using any mix of per user IP traffic and shared broadcast bandwidth. Obviously broadcast datastream can be the same bandwidth for all users on the sector, just as it is for all users on a cable TV segment.

Ah I understand now, I was assuming Metro was a 3.5GHz product. How they can afford to deploy residential customers in 10.5 is beyond me - Those radios must be costing silly money. I suppose they at least have the advantage that all they need to do is slap on a cheap cable modem for data.

[.. Watty solves the bandwidth conundrum ..]

But leaves us with business case confusion.. Anyone care to hazard a guess at the cost of the 10.5GHz CPE? more than $600? more than $800? more?
Watty, you obviously have this service at home, who is the equipment vendor? Is it also an Airspan product?

Edit: Some digging turns up 10.5GHz CPE from Alvarion and Cambridge Broadband in the $1200->$2000 range. Presumably this has to be more sophisticated on the data side than whatever Digiweb are using but the radios will be the most expensive part.