Kitz Forum

Broadband Related => Broadband Technology => Topic started by: Weaver on August 24, 2016, 04:59:46 PM

Title: G.Fast timetable / crystal ball
Post by: Weaver on August 24, 2016, 04:59:46 PM
Where are we (correction, "ye") with G.Fast? Is there any timescale or best guess estimate for when it might start to become more real?
Title: Re: G.Fast timetable / crystal ball
Post by: GigabitEthernet on August 24, 2016, 05:01:38 PM
Sometime between now and the year 2099 I would think.
Title: Re: G.Fast timetable / crystal ball
Post by: WWWombat on August 24, 2016, 05:48:52 PM
I think the aim for the pilot is at the around the start of 2017.

I don't think we'll hear any fuller plans right now, because everything has been conditional on appropriate regulation from Ofcom. Until the ink is dry on the agreements on the future of Openreach, nothing will be confirmed.
Title: Re: G.Fast timetable / crystal ball
Post by: Bowdon on August 25, 2016, 11:16:45 AM
I wonder when they will roll out G.fast modems?

This recent HH6, I'm thinking that isn't G.fast compatable?

We'll need to get one of the G.fast modems so we can get the stats working. That will be the only downside initially. Unless BT / OR decide to give us the ability to monitor stats better.
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 25, 2016, 12:21:19 PM
what are the possibilities for G.Fast modems currently?
Title: Re: G.Fast timetable / crystal ball
Post by: Bowdon on August 25, 2016, 03:29:40 PM
I noticed there are some examples of the routers used in the trials

http://www.ispreview.co.uk/index.php/2016/01/a-quick-look-at-bts-early-uk-trial-of-g-fast-broadband-routers.html (http://www.ispreview.co.uk/index.php/2016/01/a-quick-look-at-bts-early-uk-trial-of-g-fast-broadband-routers.html)
Title: Re: G.Fast timetable / crystal ball
Post by: burakkucat on August 25, 2016, 05:32:43 PM
I'll just add the comment that all current xDSL circuits operate in frequency division duplex mode whereas G.Fast circuits will operate in time division duplex mode.
Title: Re: G.Fast timetable / crystal ball
Post by: phi2008 on August 29, 2016, 03:11:48 PM
I was interested in G.fast, now not so much. They are rolling it out from the cabinet, no reduction in copper to the user and therefore no reduction in the faults/issues copper throws up - had long term issues with a previous line, a bad experience that remains with me. There must also be a price premium, another sticking point. Unless the cost of G.fast is very close  to VDSL I'm probably not going to bother.  :-\
Title: Re: G.Fast timetable / crystal ball
Post by: digitalnemesis on August 29, 2016, 08:42:22 PM
If 700 m from the cab with 50 Mbps, what should one expect on G.Fast?
Title: Re: G.Fast timetable / crystal ball
Post by: Ronski on August 29, 2016, 08:53:48 PM
AT 700m nothing I'm afraid, I'm doubtful at around 450/500 meters with my bad line, although here  (https://en.wikipedia.org/wiki/G.fast)suggests speeds of 100Mbps. G.Fast falls off even quicker than VDSL due to the higher frequencies used.
Title: Re: G.Fast timetable / crystal ball
Post by: NewtronStar on August 29, 2016, 09:43:47 PM
1000 meters from cabinet so g.fast will not change anything at my end unless a node is installed at the top of the DP or an all in one cabinet is installed 500 meters closer to my premises but sometimes pigs do fly on openreach  :-\
Title: Re: G.Fast timetable / crystal ball
Post by: Chrysalis on August 29, 2016, 10:24:21 PM
at 700m you wont even be able to sign up for g.fast.
Title: Re: G.Fast timetable / crystal ball
Post by: j0hn on August 29, 2016, 10:37:45 PM
AT 700m nothing I'm afraid, I'm doubtful at around 450/500 meters with my bad line, although here  (https://en.wikipedia.org/wiki/G.fast)suggests speeds of 100Mbps. G.Fast falls off even quicker than VDSL due to the higher frequencies used.
that's combined download/upload, so probably something like 80/20 depending on how much is allocated to the upload with G.Fast? You would probably be paying more for the same speed as someone getting max speeds on FTTC.

Does anyone know the speeds up/down OpenReach are likely to offer on G.Fast?
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 29, 2016, 11:07:04 PM
So what's the point of a city-only technology that doesn't even work well for some urban dwellers because of distance restrictions?
Title: Re: G.Fast timetable / crystal ball
Post by: burakkucat on August 29, 2016, 11:22:14 PM
Please correct me if I am wrong but I understand that G.Fast (in the U.K.) is still in the testing/trial phase.  :-\  Hence it is really quite pointless speculating upon what may or may not happen with one's own circuit . . .
Title: Re: G.Fast timetable / crystal ball
Post by: Black Sheep on August 30, 2016, 07:29:27 AM
He knows ^^^^^.  :cool:
Title: Re: G.Fast timetable / crystal ball
Post by: GigabitEthernet on August 30, 2016, 02:17:00 PM
This seems like a terrible idea. I thought the point of G.Fast was to move the fibre nearer to the home?

Talk about not future-proofing the network. In 10 years time we're going to be massively behind if this does turn out to be the rollout strategy.
Title: Re: G.Fast timetable / crystal ball
Post by: Black Sheep on August 30, 2016, 02:32:51 PM
 :wall: :wall: :shrug2:
Title: Re: G.Fast timetable / crystal ball
Post by: GigabitEthernet on August 30, 2016, 02:34:58 PM
:wall: :wall: :shrug2:

Notice I said:

Quote
...if this does turn out to be the rollout strategy.
Title: Re: G.Fast timetable / crystal ball
Post by: Black Sheep on August 30, 2016, 02:49:02 PM
Please correct me if I am wrong but I understand that G.Fast (in the U.K.) is still in the testing/trial phase.  :-\  Hence it is really quite pointless speculating upon what may or may not happen with one's own circuit . . .

Notice what burakkucat says ................ it's no use applying a caveat at the end of what is nothing more than pie-in-the-sky chat.
Title: Re: G.Fast timetable / crystal ball
Post by: GigabitEthernet on August 30, 2016, 02:54:27 PM
If they're testing G.Fast using a cabinet method, why would they suddenly launch it any other way. Your logic totally escapes me.
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 30, 2016, 03:00:01 PM
From what if anything we know about G.Fast is it likely to perform worse than older technologies over long lines? (ie. compared to what would be ‘long’ for VDSL2)

I just wondered whether this is an opportunity to get cleverer software in, or the equivalent of G.Vector, smart design that either wasn't available before, or was simply omitted for whatever reason.
Title: Re: G.Fast timetable / crystal ball
Post by: burakkucat on August 30, 2016, 03:01:50 PM
If they're testing G.Fast using a cabinet method,

"A cabinet method" is not the only mode that is undergoing testing at the various trial sites.
Title: Re: G.Fast timetable / crystal ball
Post by: burakkucat on August 30, 2016, 03:05:24 PM
From what if anything we know about G.Fast is it likely to perform worse than older technologies over long lines? (ie. compared to what would be ‘long’ for VDSL2)

There is another product named "long reach VDSL2", LR-VDSL2.

Quote
I just wondered whether this is an opportunity to get cleverer software in, or the equivalent of G.Vector, smart design that either wasn't available before, or was simply omitted for whatever reason.

No.  :no:
Title: Re: G.Fast timetable / crystal ball
Post by: niemand on August 30, 2016, 03:05:58 PM
This seems like a terrible idea. I thought the point of G.Fast was to move the fibre nearer to the home?

It was, then BT began the calls for a longer reach, lower bandwidth version and this is where we are.

Deeper fibre will I'm sure come, however according to all reports I've read BT have indeed trialed a variety of G.fast deployments and the overwhelming majority, if not all, of their deployment between now and 2020 will be cabinet/node based.

They have a target they said they'd reach, they can reach it most cheaply by deploying in this manner.

When BT spend more than they have to it's usually due to poor management or incompetence. In this instance they have a pretty modest target that can be reached with a relatively modest spend.
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 30, 2016, 03:08:52 PM
[I read a short article about LR-VDSL in use at one trial site now in Lewis, no technical details much, unfortunately.]
Title: Re: G.Fast timetable / crystal ball
Post by: Chrysalis on August 30, 2016, 04:21:40 PM
For those of us not within g.fast range from a cabinet bear in mind there is two things that may help.

1 - some areas will get copper rearrangement, its not going to be every cabinet, but some will be identified where by if its deemed rearranging cables improves cabinet coverage of g.fast large enough then it will be done, this I assume will help VDSL customers on the same cables. BT wont be doing this to boost speeds of people who can get g.fast, it is about boosting property count.
2 - Crosstalk on VDSL should reduce if people move from VDSL to g.fast.
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 30, 2016, 05:26:08 PM
Might be able to end ADSL completely too? And so improve the possibilities for VDSL2 as well.
Title: Re: G.Fast timetable / crystal ball
Post by: Chrysalis on August 30, 2016, 09:49:23 PM
unlikely as ofcom want LLU based adsl services to continue. Those are all exchange based and are a massive blocker to ditching exchange based adsl services.
Title: Re: G.Fast timetable / crystal ball
Post by: j0hn on August 30, 2016, 11:59:33 PM
The current LR-VDSL trials require the turning off of ADSL lines on the cabinets taking part in the trials.
Quote
In order to prevent  exchange  based ADSL  or ADSL2plus customers served via a  cabinet selected for  LR-VDSL  being  adversely  affected, these lines must be migrated to  an FTTC GEA  service  (either VDSL  or  LR-VDSL, depending on D-side  insertion loss measured  at 300kHz).   This means that  LR-VDSL  can be  safely deployed without  adversely  impacting  exchange  based services.
I can't see them turning off all ADSL though, or even all ADSL lines on a cabinet utilising LR-VDSL during the commercial rollout. The DSLAMs simply don't offer enough capacity to make everyone switch from ADSL to LR-VDSL/VDSL2. It's probably why they have picked very rural areas for trials.
Title: Re: G.Fast timetable / crystal ball
Post by: niemand on August 31, 2016, 12:06:13 AM
As I understand it they don't require them being turned off but they will be degraded due to the high power VDSL 2 signals sharing the spectrum with them. Previously VDSL 2 had power masking in the ADSL2+ frequency range however with this technology it doesn't.

This is trial time, though, and we know how obsessed Ofcom are by LLU even if it's holding progress back.
Title: Re: G.Fast timetable / crystal ball
Post by: j0hn on August 31, 2016, 08:46:55 AM
As I understand it they don't require them being turned off
STIN 522 specifically states it does for the trial. The quote above actually stats with

[6], special dispensation  has  been received from  Ofcom to enable  LR-VDSL  trials to be deployed at specific locations
In order to prevent  exchange  based ADSL  or ADSL2plus customers served via a  cabinet selected for  LR-VDSL  being  adversely  affected, these lines must be migrated to  an FTTC GEA  service  (either VDSL  or  LR-VDSL, depending on D-side  insertion loss measured  at 300kHz).   This means that  LR-VDSL  can be  safely deployed without  adversely  impacting  exchange  based services.


This is specifically because like you just said the usual CAL shaping and PSD masking isn't applied.
Title: Re: G.Fast timetable / crystal ball
Post by: niemand on August 31, 2016, 10:14:35 AM
Thanks for the correction.
Title: Re: G.Fast timetable / crystal ball
Post by: Chrysalis on August 31, 2016, 12:19:18 PM
I expect those areas have no LLU operators tho.

In area's where LLU operators exist there will be competition issues blocking it.
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 31, 2016, 12:21:12 PM
Thank god there is no LLU up here then. Agreed, I can't imagine there is an LLU in Lewis unless Stornoway itself is an exception.
Title: Re: G.Fast timetable / crystal ball
Post by: Chrysalis on August 31, 2016, 12:22:30 PM
If this LR-VDSL thing takes off, those areas which have no LLU may actually jump ahead of LLU areas.
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 31, 2016, 12:33:59 PM
in which case Ofcom really needs a good kick up the arse. Ridiculous to be holding progress back because of outdated bureaucratic nonsense. Getting rid of ADSL should be a general goal unless there's a technical reason or practical reason why not, or where it might stuff some users.
Title: Re: G.Fast timetable / crystal ball
Post by: Bowdon on August 31, 2016, 12:52:12 PM
I wonder how many exchanges have LLU operators these days. Most of the operators seem to have merged in to one by buying each other out.

On my exchange there is only Sky, TalkTalk, Zen and Vodafone (which was just enabled in June).

So 3 out of 4 have fibre products. I'm not sure about vodafone if they have fibre products or not.
Title: Re: G.Fast timetable / crystal ball
Post by: WWWombat on August 31, 2016, 01:59:23 PM
I wonder how many exchanges have LLU operators these days.

Market A - with only one or two principle operators - is around 9% of premises in the UK. I guess the number with access to only BT is less than this.

However, I think Market A amounts to more than 3,200 exchanges (out of 5,600).
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 31, 2016, 02:18:06 PM
BT was allowed to do FTTC and so make some real progress without the bureaucrats and meddlers trying to force the availability of some kind of sub-unbundled-FTTC or whatever onto us - is that correct?
Title: Re: G.Fast timetable / crystal ball
Post by: WWWombat on August 31, 2016, 07:04:57 PM
I'm not quite sure what "sub-unbundled-FTTC" you might mean, but...

a) BT were forced to offer VULA on their fibre products, before FTTC was allowed. That's the virtual bitstream GEA service that Openreach sells to Sky etc.

b) And separately, BT have to offer physical SLU (LLU subloop unbundling) too - allowing other companies to install their own FTTC-style cabinet. Warwicknet do this, as do Callflow.
Title: Re: G.Fast timetable / crystal ball
Post by: Weaver on August 31, 2016, 07:11:34 PM
Thanks WWombat, I'm not at all au fait with developments related to FTTC, a world forever denied to me at the moment.