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[Bowdon]

I'm not as techy as people on here. But wouldn't pushing more speed down a long copper line cause potentially more interference?

I thought the reason G.fast could operate at higher speeds was partially because the amount of copper line it had to go down would be reduced?

[Black Sheep]

A little bit (not much), more info on the original post here ....... http://btplc.com/News/#/pressreleases/openreach-expands-ultrafast-fibre-plans-1339239

[Black Sheep]

I'm not as techy as people on here. But wouldn't pushing more speed down a long copper line cause potentially more interference?

I thought the reason G.fast could operate at higher speeds was partially because the amount of copper line it had to go down would be reduced?

You're thinking is spot-on, Bowdon. That is why the distances of 300-350mtrs are being quoted as this is the maximum G.Fast will operate at. Ergo, only EU's within that same distance from their street cab will benefit initially.
As time goes by, OR will be pushing G.Fast to the remote nodes FTTDp (Telegraph poles/Underground joints) as the 'Planners' see fit to try and get as many EU's within that 300-350mtr radius.

As mentioned above ...... this is still a large-scale trial as a pre-cursor for G.Fast being pushed out to FTTDp.

[Black Sheep]

Another linky for those interested ............. http://www.ultrafast-openreach.co.uk/

[Bowdon]

I can understand why they are doing it this way. Though it looks like I'm outside of the range at just over 400 metres.

Wouldn't it be better to replace FTTC with G.fast?

Does G.fast speeds drop off faster than FTTC speeds? If not then surely everyone would get a speed boost if they converted all fttc lines to G.fast? Then in stages they could add nodes and cross each line over individually?

[Black Sheep]

I can understand why they are doing it this way. Though it looks like I'm outside of the range at just over 400 metres.

Wouldn't it be better to replace FTTC with G.fast?

Does G.fast speeds drop off faster than FTTC speeds? If not then surely everyone would get a speed boost if they converted all fttc lines to G.fast? Then in stages they could add nodes and cross each line over individually?

Are you drinking Guinness, bud ?? We've just covered the fact they cease around the 300-350mtr mark. It is far easier to deploy G.Fast technology at the existing DSLAM (FTTC Cab), than it is to a remote node. So they are doing this bit first it would seem (I'm not personally involved in any trial area), before they start to plan and implement the 2nd stage roll-out to remotes nodes ?. 

[Bowdon]

I was asking because the base frequency of FTTC is 17MHz while G.fast uses 17-106MHz (?), so I was wondering if there was a hybrid solution between the two technologies, though admittedly I don't know if that is possible. I'm trying to figure out if all the technologies can co-exist inside the cabinet.

I don't actually understand why there needs to be a big trial of G.fast from the cabinet. What needs to be done to the cabinet to enable G.fast if there are no nodes involved? Wouldn't it be a matter of changing frequences of the available MHz spectrum?

It's been mentioned previously on the forum about interference with other technologies inside the cabinet. At the time I posted that this wouldn't be a problem as the G.fast part would be outside in a node and the cabinet would be acting as a pass-through 'base'. But now if the G.fast will be stationed inside the cabinet isn't there a risk of an interference conflict between adsl, fftc and G.fast all next to each other or can they all co-exist?

PS. I'm more a cider guy!

[Black Sheep]

I'm afraid as my area isn't part of any trial, I have nothing I can give you conclusively. I'm just guessing here but I think at the actual DSLAM it would just be a simple matter of filtering through the G.Fast frequencies ....... ie: just switching them in ??
With remote nodes, they have to fit additional units and provide power and whatever other trickery is involved

As with any trial, there are umpteen different scenario's that can be presented that may affect performance. So, before they 'Go public' with what the EU might expect from G.Fast, I'm guessing they want to trial as many different scenario's as possible ?? I know I would with you lot breathing down my neck 

PS ..... love a cider with ice on a really hot day.   

[kitz]

Does G.fast speeds drop off faster than FTTC speeds?

Reasonable question to ask if it drops off quite a lot quicker... and I totally get your line of thinking when you say about stages.    Im about to walk out the door, so this is the first graph I came across which shows a comparison. You can see that after 300m then performance is be worse.

This isnt an ideal graph for comparison because it also includes vectoring, but hopefully it will help visualise just how quickly it does fall off.    If anyone can find a better example please share



link

[Black Sheep]

Just read a little bit on G.fast sited at the Cab ........ it does indeed require an actual unit to be fit, (rather than what I imagined would happen, as mooted above). These will probably be installed in a 'Side-pod' built onto the existing PCP ??

 

[William Grimsley]

Does G.fast speeds drop off faster than FTTC speeds?

Reasonable question to ask if it drops off quite a lot quicker... and I totally get your line of thinking when you say about stages.    Im about to walk out the door, so this is the first graph I came across which shows a comparison. You can see that after 300m then performance is be worse.

This isnt an ideal graph for comparison because it also includes vectoring, but hopefully it will help visualise just how quickly it does fall off.    If anyone can find a better example please share



link

What? They're only going to put G.FAST up to 400 m? That's rubbish! Install a cabinet next to my house please!

[Ronski]

I'm pretty sure they will eventually build nodes further out, hopefully right by my house to!

[Weaver]

God, it's not much use. Our village stretches out ~1530 m along a road. Trying to cover it with a 200 m radius is not going to do it. Yet more city-only technology from BT.

[Black Sheep]

God, it's not much use. Our village stretches out ~1530 m along a road. Trying to cover it with a 200 m radius is not going to do it. Yet more city-only technology from BT.

You've managed to almost half the quoted trial working distances of circa 350mtrs in one sentence, Weaver ?? Why 200mtrs pal ??

It doesn't matter how long your village is, our Planning Team will work out where to best install G.fast DPU's to capture the most EU's within a 350mtr radius. If that means installing 4/5 DPU's in your village then I'm guessing that is the intention reading the swathes of info available. They won't just be fitting one DPU per village/town/city.
 
Of course, there are always going to be instances where it is not financially viable to fit a DPU for just one or two EU's. That's business, that's life.

[Weaver]

> You've managed to almost half the quoted trial working distances of circa 350mtrs in one sentence, Weaver ?? Why 200mtrs pal ??

I was looking at the graphs and the intersection point with the other technologies shown.

> It doesn't matter how long your village is, our Planning Team will work out where to best install G.fast DPU's to capture the most EU's within a 350mtr radius. If that means installing 4/5 DPU's in your village then I'm guessing that is the intention reading the swathes of info available. They won't just be fitting one DPU per village/town/city.

Ah. That makes all the difference. If they can stand the cost of several nodes in our village then that's excellent, I stand corrected.