how long till 1gbit?

[General Maximus]

Just had a quick scan of the news and saw this:

http://www.foxnews.com/scitech/2012/03/01/surfing-at-billion-bits-per-second/?intcmp=features

I would love to have 1gbit for the sake of it but despite how much I download (about 400gb/month) I can honestly say I just wouldn't use it to it's full potential and it would sit there doing nothing 99% of the time.

We can all dream. Hopefully we'll be getting close to it within the next 10 years. It is going to be something when we can sit here and remember what it was like back on 33k dialup and then say we have now got gigabit. It will be like snail speed compared to a Concorde.

[qasdfdsaq]

BT are trialling gigabit this year and are aiming at GA in Q1 2013.

VM have trialled 1.5 gigabit but have no public plans for widespread availability anytime soon.

---------- Post added at 23:09 ---------- Previous post was at 23:06 ----------

Also all consumer ISPs business models are completely dependant on you leaving any and all connections doing nothing most of the time, that's how this whole contention thing works.

[craigj2k12]

its actually available in some places of the UK by smaller ISPs

https://hyperoptic.com/web/guest/home
http://www.venus.co.uk/go/fibre-services/leased-lines/business-fibre-internet
http://www.ifnl.net/

but for communal houses/flats and businesses

...or if you have a lot of money to spare, 10Gb/s 1:1 contention :D :D :D

http://www.fluidata.co.uk/connectivity/leased-line/

[qasdfdsaq]

10 gigabit leased lines are nothing new. We've been running four of them for over half a decade.

At that level though, you might as well just directly lease fibre. Now 100 gigabit leased lines, there's something you don't see too often.

Last time 10 gigabit was news I was still skimming trial content off porn sites because Kazaa wasn't born yet. I was 8 at the time.

[General Maximus]

i would love to be a fly on the wall and know what the plans are for the next 5 years. 200mbit is next and I would think we are going to have 400mbit by 2015 and after that probably 750 and 1gbit. The interesting thing is going to be are we really going to need that speed. Although usage is probably going to go up as more people move to tv on demand and online movies and whatever through games consoles I can't see the file sizes going up any more than they are now. I think 100mbit un-stm'd will be more than sufficient.

The funny thing is that we have got people now asking what we used 100mbit for because they are quite happy on 10mbit. What is it going to be like when we have got 1gbit?

I don't know if you read that article but the 1gbit connection it was talking about is only £44/month. I would gladly pay triple that if I could have gigabit now.

[qasdfdsaq]

I think I've mentioned before, but it's next to impossible to say what VM are going to do in 5 years. DOCSIS 3 isn't going to scale very far beyond 1 Gbit, and going beyond is going to require VM to completely overhaul how their cable network works. In similar fashion, each extra step up in speed is going to be harder and harder for VM to achieve.

On the other hand as speeds go up, so can contention ratios, as it becomes harder and harder for any individual to use the full capacity of their line for any length of time. I personally see the provision of >100mb speeds as a turning point in this regard, when your local connection will more often than not no longer be the rate-limiting hop in your internet activities. But when it comes to providing the first widely available contended gigabit service, it's not going to be VM doing it.

BT are investing heavily into their FTTx rollouts and with good reason - because they have to. But now that they have, they're massively more future-proofed than VM are. I hear each FTTC cab costs in the region of £30k to provision and they're going through a dozen a day. Each cab is fed with dedicated and uncontended gigabit fibre, with it being relatively trivial to upgrade to 10 Gb/s. VDSL2, which provides the last hop between fibre and your home, is already operating at speeds well above 100mbps and has a theoretical maximum of over 400mbps - that's uncontended dedicated bandwidth to each and every home. Gigabit DSL is just on the horizon. That provides just what it says on the tin - gigabit speeds over copper pair. Right now, only BT can backhaul that from the end of your line - VM currently only have 200-300mbps per node.

I think the biggest game changer in the next few years will be BT's Fibre on Demand. There, we're talking the possibility of business-class gigabit fibre to anyone in an FTTC area (which, by the time it's available, will be the equivalent of almost VM's entire coverage area) - and is willing to pay the install cost. Except the cost will be closer to £500 than the £5000 it currently costs for a fibre install, and prices are likely to be in-line with business class broadband too, at around £100 per month rather than the £5000+ for leased line and well under even the heavily discounted ~£1200 or so gigabit service from VM. So start saving, you might just get your wish. Anyhow, given BT are replacing a lot of FTTP plans with FTTC, I see this as a bit of a sneaky way of getting the end-user to subsidise FTTP costs, but on the other hand seeing as it cost in the region of £150 to just get a copper phone line installed until recently, £500-£1500 to future proof your home with fibre isn't that bad a price.

I'm personally more looking forward to see the next OFCOM broadband speed survey, as I think BT will come out as a huge winner in the next round. But that's only if they keep contention in check, which so far every indication suggests they will. The next step, as you say, will probably be 200 or 240mbps for VM, but given that 120mb rollout isn't going to finish for at least 14 months, 240 is quite while off. BT in the meantime are ready to flick the switch on 80/20 although theoretically they could market it as "Up to 120mb" as-is, if it weren't for the modem only having one 100mb port active.

[craigj2k12]

not to be picky as most of that info is great, but a couple of things:

- Fibre on demand will have an install cost, the £500 - £1500 cost which was an estimate has been thrown around, one BT engineer is quoted to have said the cost is more likely going to be around the £300 mark

- The monthly cost for 100mb FTTP is listed as £50 and is currently active on BTs website, so anything above that (i.e. the 300mbit product which is to be available Jan 2013) can be worked out from that price, however if VM do something stupid like sell 300mbit for £40 a month on over-contended lines then BT will have to bring prices down to compete and probably become over-contended as well which would be a shame in my eyes

- I think it would be a mistake for BT to sell anything above 80mbit on VDSL and anything above should be FTTP - a technology which (in my eyes) is long overdue, what with the massive growth in broadband speeds. I wouldnt want to see anything with the speed loss from headline speed like ADSL with future technologies. If BT were to introduce anything towards the theoretical maximum of 400mbit over VDSL then most users would probably get half of that, then we would be back to the same shoddy thing we had with ADSL "up to 24mb", "up to 400mb"

- Another marketing technique BT needs to bring in is their quality of service, as we have seen, BTs technology is able to give far lower jitter than VMs service, to be more blunt, BT Infinity has no jitter, where as VM has tonnes, and a stable low ping (apart from when the bloody DLM thinks you unplugging the modem is a fault) - this would be an interesting marketing technique as it would bring an interesting game changer and unique selling point to a lot of ISPs. When download speeds are no longer a concern, the next thing will be upload, then probably latency, then who knows but all VM seem to care about is DL speed, sacrificing upload, contention, and quality

- Another thing which someone else mentioned in another thread was that all bandwidth should be non restricted, whether that be application based or useage based, I think that is a big one, once the backbone and local network can cope with load that needs to be sorted

[ileikcaek]

IMO FTTP is the way to go and it is long overdue in this country, even charging for people to have it installed to their properties is asking too much when in the Netherlands/Sweden etc they didn't charge at all for their fiber to the home rollout and this was pretty much 10 years ago now so it proves how much ISP's here have held us back.

Would it be possible, theoretically for VM to do away with DOCSIS 3 in the future and roll out fiber on the last leg to peoples homes? I can see them having to do such a thing if they want to survive. BT offering 1Gb within a few years will be a smack in the face so VM are going to have do do more I think. Sure they have shown DOCSIS 3 to do 1.5Gb but for a long time that is going to be very expensive to achieve as a consumer product.

Another thing other countries with fiber have is completely symmetrical connections, a lot of people in the UK would kill for a symmetrical 100/100+ connection (like is available in the Netherlands for £58.50/mo) and would pay good money for it.

In short, we are getting there, but it's taken too long.

[qasdfdsaq]

not to be picky as most of that info is great, but a couple of things:

- Fibre on demand will have an install cost, the £500 - £1500 cost which was an estimate has been thrown around, one BT engineer is quoted to have said the cost is more likely going to be around the £300 mark

Yes, I did already mention that. If it's actually £300 on average, then I might even be paying less for fibre than a standard telephone install (90m from cab with only one underground run of 40m or so).

- The monthly cost for 100mb FTTP is listed as £50 and is currently active on BTs website, so anything above that (i.e. the 300mbit product which is to be available Jan 2013) can be worked out from that price, however if VM do something stupid like sell 300mbit for £40 a month on over-contended lines then BT will have to bring prices down to compete and probably become over-contended as well which would be a shame in my eyes

The 300mb product is to be available some time this spring, the 1Gbps is to become available around Jan 2013.

Pricing for the Fibre on Demand may or may not be related. As you'll recall it's primarily aimed as businesses for now so more likely to be priced in line with their business broadband services.

- I think it would be a mistake for BT to sell anything above 80mbit on VDSL and anything above should be FTTP - a technology which (in my eyes) is long overdue, what with the massive growth in broadband speeds. I wouldnt want to see anything with the speed loss from headline speed like ADSL with future technologies. If BT were to introduce anything towards the theoretical maximum of 400mbit over VDSL then most users would probably get half of that, then we would be back to the same shoddy thing we had with ADSL "up to 24mb", "up to 400mb"

Thing is, going to 100 or 200mbps on VDSL is as simple as a flick of a switch (technically) - though the latter would require new routers (note: not modems!). It'd be foolish of them *not* to when the equipment already does it. They probably won't release "Up to 400mb" on single-line VDSL but realistically could expect in the region of 150-200mbps.They already have more capacity per node and smaller nodes than VM will be using for 200mb and probably even 400mb. Don't forget they're currently selling what is actually an "up too 100mb" service at 40mb and "up to 217mb" service as 80mb to manage customer expectations - i.e. exactly the reasons you mention.

- Another marketing technique BT needs to bring in is their quality of service, as we have seen, BTs technology is able to give far lower jitter than VMs service, to be more blunt, BT Infinity has no jitter, where as VM has tonnes, and a stable low ping (apart from when the bloody DLM thinks you unplugging the modem is a fault) - this would be an interesting marketing technique as it would bring an interesting game changer and unique selling point to a lot of ISPs. When download speeds are no longer a concern, the next thing will be upload, then probably latency, then who knows but all VM seem to care about is DL speed, sacrificing upload, contention, and quality

Yes - I agree. Both latency and jitter (or lack thereof) are now more important than bandwidth when it comes to loading web-pages (and some would say, have been for quite a while). VM's modems also introduce significant bufferbloat which makes things god-awful slow when multiple users are using the connection at the same time, ironically exactly what their marketing is targeting. I'll point out BT have been quite quick to emphasize the HomeHub 3's advantages over the VM Superhub in their marketing so they do have some competent marketing folk.

- Another thing which someone else mentioned in another thread was that all bandwidth should be non restricted, whether that be application based or useage based, I think that is a big one, once the backbone and local network can cope with load that needs to be sorted

I only agree partly. I don't think at the rate speeds are going up any sort of unlimited connection that allows users to cane 100% of their speed 24/7 will be feasible under £1000 a month. Management of users based on usage is inevitable, while they keep quoting various 9x% figures 5% of users really do use 95% of capacity while paying for 5% of it...

[BenMcr]

I'll point out BT have been quite quick to emphasize the HomeHub 3's advantages over the VM Superhub in their marketing so they do have some competent marketing folkTo be honest, I don't think that BT's Marketing team are better (or worse) than any other. They are always going to claim that their product is better than others - whether that can be proved is the nub:

http://www.asa.org.uk/ASA-action/Adjudications/2012/2/British-Telecommunications-plc/SHP_ADJ_161806.aspx

[qasdfdsaq]

IMO FTTP is the way to go and it is long overdue in this country, even charging for people to have it installed to their properties is asking too much when in the Netherlands/Sweden etc they didn't charge at all for their fiber to the home rollout and this was pretty much 10 years ago now so it proves how much ISP's here have held us back.

You also pay double the taxes in those countries. ISPs have to get money from somewhere. Blame the government if you think ISPs aren't doing enough (because they have no money)

Would it be possible, theoretically for VM to do away with DOCSIS 3 in the future and roll out fiber on the last leg to peoples homes? I can see them having to do such a thing if they want to survive. BT offering 1Gb within a few years will be a smack in the face so VM are going to have do do more I think. Sure they have shown DOCSIS 3 to do 1.5Gb but for a long time that is going to be very expensive to achieve as a consumer product.

They would have to, at some point in the future, but not anytime soon. The cable going into your home can carry several gigabits easily, it's just shared between too many people and needs un-sharing.

Another thing other countries with fiber have is completely symmetrical connections, a lot of people in the UK would kill for a symmetrical 100/100+ connection (like is available in the Netherlands for £58.50/mo) and would pay good money for it.

VDSL (i.e. BT Infinity) can easily do symmetrical connections and can also manage 100/100 (assuming future profile upgrade to 30a). Most people don't want it, hence BT are rebalancing the bandplan to reduce upload speed and increase download speed, since that's what people (mistakenly) believe to be important.

In short, we are getting there, but it's taken too long.

Meh, like I said, it's all about the money.

[General Maximus]

ffs, if they are going to investigate stuff like that after on 9 complaints, 3 and 1 then the next time I see a VM ad floating the shub and unbeatable wireless performance I am going to write a nice long letter to the ASA to get that sorted. Do you think we have to wait for it to come on TV or can we challenge it based on what they advertise on the website?

[qasdfdsaq]

To be honest, I don't think that BT's Marketing team are better (or worse) than any other. They are always going to claim that their product is better than others - whether that can be proved is the nub:

http://www.asa.org.uk/ASA-action/Adjudications/2012/2/British-Telecommunications-plc/SHP_ADJ_161806.aspx
I'd say they're better than many others, but that's personal opinion. Whether the wireless is any more or less reliable than the Superhub we'll find out soon, but yes, claiming you're better than everything is in most cases unsubstantiated and a step to far. But they have clearly been playing on the perceived weaknesses of their main competitor.

[Andrewcrawford23]

i probally say before virign go to true fibre to the hime they probally split the node down so instead of i think 500 cusotmer per node it might be 200 so the bandwidht is shared more not sure if that be chepae rthan go straight ot fibre they might also offer a fibre on demand like bt you pay them to install it they will give oyu it

[qasdfdsaq]

I thought they were already aiming at a 250-homes-per-node target

[Andrewcrawford23]

I thought they were already aiming at a 250-homes-per-node target

im not sure i know it somewher ebetwen 200-500 i think it depend son areas hence some are worse than others

[craigj2k12]

yeah some areas are worse off in that respect but qas is talking about the target number per node

[Sephiroth]

Just had a quick scan of the news and saw this:

http://www.foxnews.com/scitech/2012/03/01/surfing-at-billion-bits-per-second/?intcmp=features

I would love to have 1gbit for the sake of it but despite how much I download (about 400gb/month) I can honestly say I just wouldn't use it to it's full potential and it would sit there doing nothing 99% of the time.

We can all dream. Hopefully we'll be getting close to it within the next 10 years. It is going to be something when we can sit here and remember what it was like back on 33k dialup and then say we have now got gigabit. It will be like snail speed compared to a Concorde.
Coming back down to earth from the general discussion so far in this thread, the FOX article is very incisive. It points out that 1Gb/s downloads are just not to be expected. My remarks below are confined to the VM network.

The reason for this, apart from the rate limiting or whatever is used by a distributor to control demand, pretty well guarantees that there's little premium value for downloads in a 1 Gb/s service.

The second point that could well perplex the likes of VM would be peering arrangements and the costs of raising the bandwidth to keep customers happy. We all know that VM keep these costs (and hence bandwidth) to the minimum they can get away with.

Third, there are potential consequences for VM's core since each connection would be able to punt in at 10 x what they can do now (subject to congestion at the oprical node LOL).

Finally on VM's 1.5 Gb/s trial - I haven't been able to glean what they've actually done. They say it's on a standard infrastructure; but they haven't disclosed the QAM number nor any amount of detail that would make it worth knowing that they've done this.

[qasdfdsaq]

The reason for this, apart from the rate limiting or whatever is used by a distributor to control demand, pretty well guarantees that there's little premium value for downloads in a 1 Gb/s service.
This reminds me of something I'd thought of as well - the only likely way for any one user to take up the full 1Gbps capacity would be the likes of BitTorrent - which downloads simultaneously from many different hosts in many different locations in the way HTTP downloads, by default, do not. I do wonder then, if availability of such connections would likely cause a resurgence in the level of P2P use.

[Andrewcrawford23]

This reminds me of something I'd thought of as well - the only likely way for any one user to take up the full 1Gbps capacity would be the likes of BitTorrent - which downloads simultaneously from many different hosts in many different locations in the way HTTP downloads, by default, do not. I do wonder then, if availability of such connections would likely cause a resurgence in the level of P2P use.

acutally a lot of http downloads now a days use a p2p model, not that they use the user downloading to upload in more that says for a linux ditro ther eis multiply host for the file they have some sort of program or code set up that when you start downloading it it then connects to peers

dnt ask me how they do it as a http download should only ever use one conenction adn oyu need a download manager to use more than one host but they seem to have developed something server side that does the same

so if that sort of things is rolled out with majority of websites then 1gbit could be archive easily

i cant remebre the site that i found that was doign this multi conneciton http download but it wsnt a linux distro it was jsuta example

how did i find out it was doing it i was packet capturing data at th etime looking for some information sinc ei suspect i might have a trojen on my system at the time

[qasdfdsaq]

acutally a lot of http downloads now a days use a p2p model, not that they use the user downloading to upload in more that says for a linux ditro ther eis multiply host for the file they have some sort of program or code set up that when you start downloading it it then connects to peers

dnt ask me how they do it as a http download should only ever use one conenction adn oyu need a download manager to use more than one host but they seem to have developed something server side that does the same

so if that sort of things is rolled out with majority of websites then 1gbit could be archive easily

You might be thinking of load-balancers. They're nothing like P2P downloads and have no effect on the actual connections between the server and the end user, only what invisibly goes on behind the server.

Short of a download manager, what you're saying isn't possible

[Andrewcrawford23]

You might be thinking of load-balancers. They're nothing like P2P downloads and have no effect on the actual connections between the server and the end user, only what invisibly goes on behind the server.

Short of a download manager, what you're saying isn't possible

nothing is impossible, but i do take your point it most like aloa blanacer, , acutally in thoery i could possible scritp code that do excately wha ti said above but it then make the server a client so it would be downloading from multiply sources and passing that speed to you as i say in thoery how i script that in pratice i aint sure not really lookin to do it not unless i am paided

[General Maximus]

They say it's on a standard infrastructure; but they haven't disclosed the QAM number nor any amount of detail that would make it worth knowing that they've done this.

I have been reading more about QAM and trying to understand what it is and how it works. I found a paper last night (and I cant find the link for it now) which was discussing alsorts of stuff to do with the problems with noise, snr and how you would calculate BER (can't remember what that is either).

The thing which caught my eye and why i was looking to start off with is how you calculate the throughput on a line for each QAM number. They gave 2 examples:

QAM64 = 2^6 = 64bits. 6 (the power) * 5 = 30mbits per channel
QAM256 = 2^8 = 256bits. 8 (the power) * 5 = 40mbits per channel

I am a bit confused because I don't understand why we are multiplying the power by "5" and for whatever reason I would have thought that it should be more around 7 because I thought QAM256 was 55mbits per channel and not 40.

I await your words of wisdom Seph :nworthy:

[ileikcaek]

^^ most likely those figures are for the DOCSIS they use in the US and not EU DOCSIS which we use here. DOCSIS has less bandwidth than EU DOCSIS.

DOCSIS = 42.88Mb/s per channel
EU DOCSIS = 55.62Mb/s per channel

[General Maximus]

cool, so I was right with the x*7 then.

That means for 1gbit we would be looking at QAM2048 for 1gbit and QAM4096 for 1.5gbit. Now I just need to understand how SNR comes into it :)

[Andrewcrawford23]

cool, so I was right with the x*7 then.

That means for 1gbit we would be looking at QAM2048 for 1gbit and QAM4096 for 1.5gbit. Now I just need to understand how SNR comes into it :)

if you are using shub as a exmplae then yes, but to go to such qam would reuqire a much strict torlance in upstream and downstream power levels i cant remember what extcately in fac tno sute that qam4096 exist

to achive 1.5gbit virign used a modem capable of bonding up to 32 channels so 32*55mbit but comcast i think have tested a 64 bonding one and i think tested at qam1024i think they achive about 4gbit

[General Maximus]

I didn't think about that. It is probably easier for them just to stay on QAM256 now that they have got the network sorted for capacity and power levels etc and just bond more and more channels. They could offer up to 800mbit with a 16 channel modem.

[Andrewcrawford23]

not saying it impossible they wont go beyond qam2546 as i have noticed a lot fo work that has improve power levle sin my area drastically my area had a issue with upstream stuck beyond 58-61 they done work at the headend and brought it down to about 53 now they have done mroe owkr and brought it down to 40, the downstream has been changinga lot recently to from 6 to -8 now about -2

[qasdfdsaq]

Going beyond QAM256 is indeed, a lot of work for very little gain, and well into the realm of diminishing returns. Very few public/consumer networks use anything above QAM256.

Going from QAM256 to 1024 for example requires your equipment to be four times more precise while only giving you 25% more throughput. QAM4096 requires 400% better precision again, with only 20% gain.

[General Maximus]

maybe they could do a bit of both and go to something like QAM512 and 16 channels

[qasdfdsaq]

QAM512 only gives you 12.5% more capacity than QAM256. Which means only ~62mbps per channel.

[General Maximus]

I know, I thought they wouldn't have to worry about the noise so much and it gives them 500mbits (nice number) on 8 channels and 1gbit on 16 channels. Seems like a nice all rounder

[qasdfdsaq]

They'd have to worry about it twice as much as they do now - and some areas are still struggling to get beyond QAM64 let alone 256.

Also, the Superhub wouldn't work on it, nor would any other modems currently in use.

[Andrewcrawford23]

Going beyond QAM256 is indeed, a lot of work for very little gain, and well into the realm of diminishing returns. Very few public/consumer networks use anything above QAM256.

Going from QAM256 to 1024 for example requires your equipment to be four times more precise while only giving you 25% more throughput. QAM4096 requires 400% better precision again, with only 20% gain.

is that 20% on top of qam1024 or qam 256? if it 20% form qam256 then it seem pointless sicne oyu get less bandwidth than going o qam1024

[qasdfdsaq]

20% on top of QAM1024.

[Andrewcrawford23]

20% on top of QAM1024.

thought as much clears for clearing that up

[General Maximus]

maybe they should judt knock it all on the head now and start planning for fttp

[BenMcr]

maybe they should judt knock it all on the head now and start planning for fttpWho says they aren't doing so?

[qasdfdsaq]

Oh I'm sure somebody in the company is planning it. But as I've said, VM have less need for it in the medium term than BT do. And it's not cost-effective right now for either of them.

---------- Post added at 17:06 ---------- Previous post was at 17:06 ----------

Who says they aren't doing so?
Yeah, what he said.

[General Maximus]

good, at least somebody is looking to the future and come with a decent idea rather than short term solutions.

[craigj2k12]

Who says they aren't doing so?

reveal.........

[BenMcr]

reveal.........I've got no insider knowledge howeer Virgin Media have been involved in the Fujitsu trials, which are FTTP.

So Virgin must have a way of using FTTP with the existing services - probably some sort of mini fibre to coax converter that is just closer to the property than the normal local nodes are

[General Maximus]

now that is an interesting point. If they cant be bothered with all the work and hassel involved in such a huge project and changing fibre why not pay fujitsu to do it all for them? Sounds like a perfect match to me.

[BenMcr]

now that is an interesting point. If they cant be bothered with all the work and hassel involved in such a huge project and changing fibre why not pay fujitsu to do it all for them? Sounds like a perfect match to me.Again with the negativity.

Who said they can't be bothered? There is a whole world of difference between wanting to and needing to.

No company is going to spend significants amounts of money doing something they don't need to do, before they need to do it.

[Sephiroth]

I have been reading more about QAM and trying to understand what it is and how it works. I found a paper last night (and I cant find the link for it now) which was discussing alsorts of stuff to do with the problems with noise, snr and how you would calculate BER (can't remember what that is either).

The thing which caught my eye and why i was looking to start off with is how you calculate the throughput on a line for each QAM number. They gave 2 examples:

QAM64 = 2^6 = 64bits. 6 (the power) * 5 = 30mbits per channel
QAM256 = 2^8 = 256bits. 8 (the power) * 5 = 40mbits per channel

I am a bit confused because I don't understand why we are multiplying the power by "5" and for whatever reason I would have thought that it should be more around 7 because I thought QAM256 was 55mbits per channel and not 40.

I await your words of wisdom Seph :nworthy:

Mon General

256QAM is 8 bits/symbol. The downstream is 6.952 Msym/sec at 8 MHz EuroDOCSIS (and 3/4 of that at 6 MHz DOCSIS bandwidth). so 8 * 6.952 is 55.616 Mbps per channel.

On a deeper point raised in connexion with BER, the "universal" target for any modulation is that the BER (risk) should not exceed 10^-8. It's easier to achieve at 16QAM than 64QAM or 256QAM because the bit density is lower at 16QAM (remember the potholes in the road analogy).

I'd like to draw your attention to the attachment which discusses impairment risks between 64QAM and 256QAM. The argument there runs valid for higher modulation speeds, which other posters have touched on.

Table 4 in the attachment shows that for 64QAM, the target BER is likely to be breached at c. 27dB SNR; for 256QAM the same risk occurs at 33 dB SNR under lab conditions. We know those figures from our forum advice. (Although it should be pointed out that lab conditions and real life are not the same).

Cheers

[craigj2k12]

I've got no insider knowledge howeer Virgin Media have been involved in the Fujitsu trials, which are FTTP.

So Virgin must have a way of using FTTP with the existing services - probably some sort of mini fibre to coax converter that is just closer to the property than the normal local nodes are

the fujitsu trial was to be a completely separate network for rural areas in which VM would resell Fujitsu's bandwidth

[General Maximus]

I know and that is what I was thinking. If VM havent got the dough to do it atm and want to concentrate on maintaining what they have got for the next 2 years (and bang out 200mbit) why not let Fujitsu lay all the fibre and do the hard work and then buy it back off them when they are finished.


Anyways, thanks for the info Seph :tu:

[BenMcr]

the fujitsu trial was to be a completely separate network for rural areas in which VM would resell Fujitsu's bandwidthYup, but the end product is the same that is available within the core cable network - it wasn't the Virgin National products set.

Virgin Media doesn't have the same bottleneck that BT does, so even using FTTP doesn't mean there is an immediate advantage

[General Maximus]

Yup, but the end product is the same that is available within the core cable network - it wasn't the Virgin National products set.

Virgin Media doesn't have the same FTTP bottleneck that BT does, so even using FTTP doesn't mean there is an immediate advantage

so what are we looking at then? Increasing the fibre going from the street cabinets to the cmts and from the cmts to wherever is next?

[BenMcr]

so what are we looking at then? Increasing the fibre going from the street cabinets to the cmts and from the cmts to wherever is next?Ok. This might be a bit complicated

For the core Virgin Media network, there is zero need to push fibre further down the network for many years to come. The physical cable is more than capable of providing faster speeds than is currently available. The bigger issue within the core network is what is at each end of the cable i.e. the modem and/or the CTMS

However, if Virgin Meida want to expand into other areas, then different network topology needs to be considered. So if Virgin Media decide to use/rent the FTTP Fujtisu network (if built), then when within the network it goes from fibre to coax moves from a local node, to closer (or at) a customer's address.

It doesn't suddently mean that FTTP addresses get faster broadband that the HFC addresses, because there isn't any need to retail different products, and the end technology is still DOCSIS.

The only difference is to where the change from fibre to coax happens

[General Maximus]

i understand that and got back to my original question again. The issue isn't with the line coming out of the customers house, it is the contention at the cabinet and cmts and more capacity needs to be added.

[craigj2k12]

i understand that and got back to my original question again. The issue isn't with the line coming out of the customers house, it is the contention at the cabinet and cmts and more capacity needs to be added.

^ what he said, Ben seems to disagree

plus, I thought fujitsu's network was a complete separate network to be resold in the same way BTs is, and it would be FTTP (n.b. DOCSIS isnt FTTP)

[Andrewcrawford23]

^ what he said, Ben seems to disagree

plus, I thought fujitsu's network was a complete separate network to be resold in the same way BTs is, and it would be FTTP (n.b. DOCSIS isnt FTTP)

fujistu network will be it will be in teh rural areas, i think waht general might have been impl not read the last 20 odd posts but did read the lst one about fujistu doign it, is they will have the experiance and they are already workign with them so might be chepaer and better job

[General Maximus]

exactly, and all VM have got to do is sit back and let them crack on with it knowing they are going to do a top notch job and cough up some dosh in the end

[qasdfdsaq]

Ehm, FTTP is an expensive business, and nobody's going to crack on doing a good job if there's no guarantee of money at the end of it.

[BenMcr]

and it would be FTTP (n.b. DOCSIS isnt FTTP)My understanding is that DOCSIS would work as long is there is some coax in the mix

So could still be used in an FTTP install as long at some point it went from fibre to coax

Even if Virgin Media were to suddenly start running fibre to each propertly, all of their existing customer equipment expect co-ax, so unless Virgin create a whole new set of kit again just for FTTP installs (which I can't see being cost effective), it would still be coax in the house

[Andrewcrawford23]

My understanding is that DOCSIS would work as long is there is some coax in the mix

So could still be used in an FTTP install as long at some point it went from fibre to coax

Even if Virgin Media were to suddenly start running fibre to each propertly, all of their existing customer equipment expect co-ax, so unless Virgin create a whole new set of kit again just for FTTP installs (which I can't see being cost effective), it would still be coax in the house

it wouldnt be fttp if coax was used it be fttb

as for the house a true fttp just has ethernet port to plug into well th ones i have seen, all vrgin would nee dto do is deploy a mini node in the house ie the one that converts teh fibre to coax for tv and they a a direct plug for itnernet into the fibre

[qasdfdsaq]

DOCSIS could be used over pure FTTP. The only coax that's needed would be from the ONT to any STBs/old modems that only have coax connectors. So basically what you just said.

Three things to note:
1) Fibre is only an advantage if you actually use it to do something copper can't. DOCSIS isn't one of those things
2) Fibre does offer advantages unrelated to speed though - longer range, immunity to RF interference, less need for amplifiers, etc. that reduce network running costs and faults, as well as increasing usable capacity.
3) In a network like VM's, rather than re-doing everything, they'll probably take a hybrid approach. Starting off with something like this:

http://www.motorola.com/staticfiles/Video-Solutions/_Documents/static%20files/Leveraging%20RFoG%20to%20Deliver%20DOCSIS%20and%20 GPON%20Services%20over%20Fiber.pdf

---------- Post added at 11:39 ---------- Previous post was at 11:37 ----------

it wouldnt be fttp if coax was used it be fttb

as for the house a true fttp just has ethernet port to plug into well th ones i have seen, all vrgin would nee dto do is deploy a mini node in the house ie the one that converts teh fibre to coax for tv and they a a direct plug for itnernet into the fibre
See link above. Technically if the fibre enters the premesis, it's FTTP. Even "true" FTTP deployments currently have a ONT in the house somewhere that converts it to copper - whether that copper is UTP or coax I couldn't care less, it's still FTTP.

[Andrewcrawford23]

DOCSIS could be used over pure FTTP. The only coax that's needed would be from the ONT to any STBs/old modems that only have coax connectors. So basically what you just said.

Three things to note:
1) Fibre is only an advantage if you actually use it to do something copper can't. DOCSIS isn't one of those things
2) Fibre does offer advantages unrelated to speed though - longer range, immunity to RF interference, less need for amplifiers, etc. that reduce network running costs and faults, as well as increasing usable capacity.
3) In a network like VM's, rather than re-doing everything, they'll probably take a hybrid approach. Starting off with something like this:

http://www.motorola.com/staticfiles/Video-Solutions/_Documents/static%20files/Leveraging%20RFoG%20to%20Deliver%20DOCSIS%20and%20 GPON%20Services%20over%20Fiber.pdf

---------- Post added at 11:39 ---------- Previous post was at 11:37 ----------


See link above. Technically if the fibre enters the premesis, it's FTTP. Even "true" FTTP deployments currently have a ONT in the house somewhere that converts it to copper - whether that copper is UTP or coax I couldn't care less, it's still FTTP.

wow that thing is pretty small and basically does what i was saying

true fttp to me is a connection with fibre to the property and for internet you plug right intot he box in the house without needing coax etc but if you have the node basically in your house then congestion should be easied a lot and the bandwidht should be achivable

[kwikbreaks]

Jees is this one still running? Sorry for being lazy but has anybody asked the really important question yet - will my VMNG300 support 1GB? :)

[Andrewcrawford23]

Jees is this one still running? Sorry for being lazy but has anybody asked the really important question yet - will my VMNG300 support 1GB? :)

no it wont not unless they got the channel bandwdiht up to 250mb each which would reuire some insane qam with perfect power levles so no it wont shub will be needed for anything over 200mb but whether virign let you use vmng300 for 100-200mb in the itnrim is anyone guess

[qasdfdsaq]

Jees is this one still running? Sorry for being lazy but has anybody asked the really important question yet - will my VMNG300 support 1GB? :)
No.

---------- Post added at 11:57 ---------- Previous post was at 11:56 ----------

no it wont not unless they got the channel bandwdiht up to 250mb each which would reuire some insane qam with perfect power levles so no it wont shub will be needed for anything over 200mb but whether virign let you use vmng300 for 100-200mb in the itnrim is anyone guess
If they got the "insane qam" up that high it would stop working on the VMNG300 and require a new modem, so still no.

[AndyCalling]

Just to add my bit. 1gig is very useful, mainly because we'd get 100meg upstream and could then effectively extend our home lans over the internet via vpn and access them remotely at the same speed we do at home. Well, except for gigabit devices. When oh when will VM wake up to the need for gigabit upstreams? I suppose a 10gig connection will have to come to VM before we get that. Come on VM, get back to the days of >5 times BT speed soon, they're catching up fast...

[kwikbreaks]

no it wont not unless they got the channel bandwdiht up to 250mb each which would reuire some insane qam with perfect power levles so no it wont shub will be needed for anything over 200mb but whether virign let you use vmng300 for 100-200mb in the itnrim is anyone guessThat wasn't what I asked - what I asked was has anybody asked yet. Perhaps you missed the :)

[Andrewcrawford23]

That wasn't what I asked - what I asked was has anybody asked yet. Perhaps you missed the :)

sorry i didnt think you where asking if it was asked was teh question i thuht you where asking has it been asked if so what the answer

---------- Post added at 14:24 ---------- Previous post was at 14:23 ----------

Just to add my bit. 1gig is very useful, mainly because we'd get 100meg upstream and could then effectively extend our home lans over the internet via vpn and access them remotely at the same speed we do at home. Well, except for gigabit devices. When oh when will VM wake up to the need for gigabit upstreams? I suppose a 10gig connection will have to come to VM before we get that. Come on VM, get back to the days of >5 times BT speed soon, they're catching up fast...

100meg upstream wotn see that fora long time i say 2016 bt doesnt offer that high a upstream so why would virign want to upstream isnt the one they sell it downstream

[qasdfdsaq]

There's no need for gigabit downstream to get 100mb upstream (or even gigabit upstream). The 10:1 ratio favoured by VM is a business decision, not a technical one. You could have 100mb upstream and 10mb downstream in theory.

[Andrewcrawford23]

There's no need for gigabit downstream to get 100mb upstream (or even gigabit upstream). The 10:1 ratio favoured by VM is a business decision, not a technical one. You could have 100mb upstream and 10mb downstream in theory.

ive always wondered waht teh pign adn jitter of sucha connection would be like and it bea funyn connection at that takes ages to download but oyu can upload miels faster

[AndyCalling]

Yea, an inverted 10:1 would be interesting but unlikely. I'm guessing we never get beyond the current ratio unless we go sync like other countries have. I would settle for 100meg both ways for now, with gigabit both ways in a couple of years. That would really change the internet as we all drop the big cloud providers like Google in favour of setting up community collectives online. Back to frontier internet, cool.

If VM want to get back their massive speed advantage over BT they need to do far more than 120 down 12 up. When it was 50 versus 8 VM were unbeatable. If 4G is the miracle claimed, they will need to hurry. A sync 100/100 advertising 'lan speed over internet' would sell well, especially when people realise what it means to internet use. It'll change everything.

[Skie]

VM have a few choices with upgrade paths. The most sensible one is probably a slow roll out of FTTP with the Fibre to Coax converters in peoples houses rather than at nodes. Once that is largely done, then another slow roll out of IPTV/Telephony by switching areas over to pure Fibre (probably enabled by an all singing all dancing IPTV platform, perhaps if TiVo ever get off their backsides and create one of their own). Then you still have a few legacy customers on the HFC network which could be slowly decommissioned.

They could keep with their current infrastructure and continue investing in more and more HFC kit to keep up with bandwidth demand, but I honestly can't see that being viable in 10 years time when BT have Fibre everywhere.