Kitz Forum
Broadband Related => Broadband Technology => Topic started by: Weaver on September 12, 2019, 09:31:52 AM
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What do you think the future holds for those of us who do not have FTTC or FTTP, and are using ADSL on EO lines?
I would like to keep it to information and opinions about wired successor technologies, as opposed to prescriptive advice such as ‘switch to 5G’. My question isn’t personal. It’s rather about where do you see wired internet access going for the likes of me in general; those not caught up in the FTTx rollout.
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Well, if we are committed to turning off all copper based PSTN, that also implies ADSL one day will be shutdown, as will FTTC, it'll all be FTTP?
Alternatives to that, no sure, 5G? But I'm sceptical. Not sure how it can be a replacement for those of us who consume a lot of bandwidth because cell carriers don't typically offer "unlimited" bandwidths.
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Well, if we are committed to turning off all copper based PSTN, that also implies ADSL one day will be shutdown, as will FTTC, it'll all be FTTP?
Alternatives to that, no sure, 5G? But I'm sceptical. Not sure how it can be a replacement for those of us who consume a lot of bandwidth because cell carriers don't typically offer "unlimited" bandwidths.
That seems to be changing https://www.4g.co.uk/news/unlimited-data/ although your performance will vary by area.
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I’d specifically like to make 4G / 5G off-topic and let that important discussion go into a worthy but different thread.
Do you see an end to ADSL and EO lines in x years? Will it drag on forever ? Like analogue tv did, and like ridiculous things such as fax are doing. If it is replaced how will it get done - practically and politically?
I’m in Scotland and there may have been various claims made about service - I can’t remember. But hand-waving is one thing and making something actually happen is another. And then there’s always the strategy of "oh, yes, but I actually meant to say ‘apart from the really difficult bits’ obviously; they’re too hard and not important anyway"
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Hi
Do you see an end to ADSL and EO lines in x years?
The simple answer of course is Yes. We already know this as BT Openreach have said it, they want rid of copper, and will sell off the land/exchange buildings as soon as they are decommissioned.
Will it drag on forever ?
The simple answer is No, it will not drag on forever.
If it is replaced how will it get done - practically and politically?
Ultimately you get told to migrate to something else or get cut off. If there is no other service available to you the rules of USO would kick in, whatever they are at that point in time.
Don't forget analogue TV did get turned off.
Fax machines, well no one has said they can't be used anymore, and they would still work post PSTN via an ATA device. :-)
Regards
Phil
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What do you think the future holds for those of us who do not have FTTC or FTTP, and are using ADSL on EO lines?
Your ADSL isn't going anywhere anytime soon.
If you're asking what's next if not FTTP/FTTC then under the USO it's 4G.
Very little publicly funded FTTC now with a preference for FTTP but the most remote areas will have a long wait or not get it at all.
When they do get round to turning off copper xDSL services if they haven't yet rolled out FTTP to you then it likely need to be a wireless solution of some kind.
Either 4G, fixed wireless or satellite.
LEO satellites sound promising.
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Well, if we are committed to turning off all copper based PSTN, that also implies ADSL one day will be shutdown, as will FTTC.
That's confusing 2 different things though.
xDSL services will still be working and actively sold (probably for many years) after the PSTN switch off.
SOGEA (aka naked DSL) is about to hit the market with either no voice service or ISP provided VOIP.
OpenReach are only just starting to trial an FTTP only exchange in Salisbury.
It will take years to get to the point where they can issue a stop sell on copper services on that 1 exchange, and probably years more to migrate all existing customers over to FTTP.
There's no copper switch off happening this decade imo. PSTN is a different thing.
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I'm really not. PSTN is being switched off, as are all copper lines. You are right, this decade, it's for 2025.
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Hi
xDSL services will still be working and actively sold (probably for many years) after the PSTN switch off.
ADSL will be turned off first and not that far in the future, and probably on an exchange by exchange basis. VDSL/G.Fast will be available for a longer time, but the emphasis will be to turn-off ADSL ASAP, transferring those customers instead to VDSL. If an exchange only line, it will be converted. A lot of exchanges don't have anything to do with VDSL/G.Fast in their area as that fibre often goes back somewhere else, so once PSTN is off, it's not viable to just keep an exchange open if it is only for an ever smaller percentage of ADSL customers. Openreach will want to get the exchange closed and sell the land/building to recoup some money from their now unused assets.
Of course a lot depends on how the trial exchange areas go with their copper switch off, i.e. Salisbury. I think Openreach underestimate the work involved to connect people up to FTTP, it's one thing "passing" premises, but an entirely another thing to connect them up. A friend has been waiting 3 months for their native FTTP to be connected, now waiting for ducts to be unblocked, and this is a cul-de-sac with no issues with road closures. Several orders have gone in on the same street and not a single person as been connected in 12 weeks.
Regards
Phil
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I've consulted my crystal ball, the same one I use to win the lottery every time I need a topup ::)
They'll bring back long range VDSL and stick a cabinet at the junction of the A87 and the road to Heasta, solely for all the lines down there.
Bear in mind that if adsl is ceased, local loop unbundling will no longer be an issue for long range VDSL.
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I'm really not. PSTN is being switched off, as are all copper lines. You are right, this decade, it's for 2025.
A source to back up this absolute nonsense? PSTN is being retired, copper retirement is long after 2025.
What will they do with everyone without FTTP?
edit: Salisbury is targeted to have a copper switch off in 2025.
https://www.ispreview.co.uk/index.php/2019/07/ofcom-tests-new-regs-on-openreachs-fttp-exchange-upgrade-trial.html
and that's only the very 1st exchange for this to be trialled on.
Then they have the rest of the country to complete.
Thinking copper is being switched off nationwide in 2025 isn't just misinformed, it's deluded.
OpenReach copper still be a thing in 2030.
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OK, my mistake -
Suffice to say that this move from a heavily regulated copper network to a new FTTP platform presents more than a few challenges. Some of that work, such as the gradual switch from analogue phone (voice) services to an all-IP (VoIP etc.) style network, are already taking place and should complete by 2025.
However the physical switch-off of copper will be a much longer and more complicated process. Indeed it’s highly likely to take longer than the Government’s current aspiration of 2033 for “nationwide” coverage of FTTP.
https://www.ispreview.co.uk/index.php/2019/03/openreach-consults-uk-broadband-isps-on-copper-switch-off.html
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Hi
I think E-Side copper retirement will happen in more places and at a faster pace than full copper retirement. Once there is no PSTN and everyone is on VDSL/FTTP/G.Fast from their local cabinet, the E-side copper is redundant and the exchange is just humming to itself. If the exchange doesn't have FTTP terminated there, it's basically mothballed and sold. Being able to remove redundant E-Side copper also helps free up duct space for further full deployment of FTTP or sharing agreements, and the copper can be sold of course.
I suspect D-Side copper will remain around and in use much much longer, but ADSL will die the soonest out of xDSL technologies.
Regards
Phil
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E-Side copper is likely to remain for SOGEA products, post PSTN shutdown.
The E-Side is necessary to run all line tests for xDSL based services.
That includes ADSL products, VDSL2 products and G.Fast.
I would expect the E-Side to remain until the D-Side is removed.
I've seen nothing to suggest otherwise and testing can't be done from the DSLAMs so I see no other way getting round that.
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I think it's possible to get line cards for DSLAMs that do have their own test facilities. A few years ago Openreach swapped out (https://forum.kitz.co.uk/index.php?topic=15205.0) one type of line card that had its own test facilities because they were getting in the way.
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Indeed.
I can't see OpenReach finding a feasible way to run reliable, streamlined line tests from DSLAMs from multiple vendors.
They have a working solution as the moment.
Easier to just leave E-Side recovery till copper is fully retired and recover the whole lot at once.
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I can't see any reason why Openreach couldn't do it if they wanted to. I don't think it would be wildly different than how the DLM interacts with different DSLAMs. There's the ITU-T G.996.2 document on line testing, which will be what the different vendors will have implemented. Currently quite a lot of the information returned in the GEA service test already comes from the DSLAM (or from the modem via the DSLAM).
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Could someone clarify for me how BT might sell off eg the Broadford exchange? Won’t some physical locations for interconnects to aggregation links be needed somewhere?
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Hi
E-Side copper is likely to remain for SOGEA products, post PSTN shutdown.
The E-Side is necessary to run all line tests for xDSL based services.
That includes ADSL products, VDSL2 products and G.Fast.
I would expect the E-Side to remain until the D-Side is removed.
I've seen nothing to suggest otherwise and testing can't be done from the DSLAMs so I see no other way getting round that.
No E-Side, no ADSL so no tests required for that. FTTC/G.Fast do their own testing from the cab, you can't test much about VDSL/G.Fast from the E-Side/Exchange when the data signal is injected at the cabinet, and filters stop the signal from back tracking into the E-Side.
All you can do from the E-Side is check if PSTN is working, which checks the physical status of the line, and those tests are going to become irrelevant when there is no PSTN, plus finding a fault with such a test and sending an engineer out who finds an E-Side fault on the line, well that's a waste of time if nothing is being delivered from the exchange.
Regards
Phil
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Hi
Could someone clarify for me how BT might sell off eg the Broadford exchange? Won’t some physical locations for interconnects to aggregation links be needed somewhere?
I didn't say they would sell every exchange.
Fibre may not be delivered from your local exchange. Local exchanges were only required because of the way the public switched telephone network works, and it made sense and was the only practical way to deliver a telephone service, by having local areas have their own exchange, plus the kit to make it work takes up a lot of space, or did originally when it was mechanical switches, so that kit had to be distributed across the UK local to where it "switched the calls" to that area.
With data and fibre, you don't need the physical space, and it can run for many miles back to a destination. Think about Virgin Media or other data only suppliers, they've managed perfectly well without having "exchanges" in every town.
So when installing fibre for VDSL, and aggregation nodes for FTTP, BT choose certain exchanges to be a "point of presence" and the fibre terminates there, completely bypassing, in many cases, the local telephone exchange.
Therefore once the exchange is no longer supplying ADSL or PSTN services, it's doing nothing at all. They just turn the lights off, rip the kit out for scrape value most likely, and put the land/building up for sale.
Regards
Phil
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Line testing to check the physical status of the line would still be needed. You'd still want to find things like a break in the network and its approximate location, so you could send someone out to fix it without having to book an appointment for a home visit. Otherwise you'd have situations with no sync, can't determine what or where the problem is, and would have to book a home visit appointment.
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It’s likely that BT haven’t owned the Broadford exchange for years.
BT sold most of their exchanges back in 2001: https://www.telegraph.co.uk/finance/2743456/Property-sale-to-cost-BT-40m-a-year.html
It’s now in the process of selling off 90% of its remaining property estate:
https://www.theguardian.com/business/2019/jun/05/bt-to-close-offices-in-more-than-270-uk-locations
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Philip, I just assumed that fibre comes into say an exchange and then goes out again from there to the FTTC cabs ? And I assumed that you need some dry enclosed place to make the fibre-fibre interconnects or to park switches or L2 routers or whatever ? Where am I going wrong? I realise that I know nothing about the further upstream fibre-side topology of FTTx, upstream of the green cab.
If for example there is a link to another more important ‘new POP’ exchange from a minor local one, are we saying that all FTTC cabs would have new long fibre links to the new POP even though it is much much further away? Apologies for being stupid.
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In many areas, not just rural locations, FTTC cabs connect to a head end exchange where the routers and switches are situated. The fibre links may not go anywhere near the local PSTN exchange. My head end exchange is about 12 miles away.
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@RealAleMadrid Just to check my understanding; is it the case that when the FTTC cabs were put in in your area, the fibre feeds to them were originally put in running all the way direct to that PoP 12 miles away?
I was however talking about a case when this was not so originally; where hypothetically the PoP is at the nearest exchange anyway. But let’s say BT wanted to completely get rid of that exchange ; what would happen then ? A costly rerouting or else just decide not to bother to do it at all, because of the costs involved ?
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FTTC/G.Fast do their own testing from the cab, you can't test much about VDSL/G.Fast from the E-Side/Exchange when the data signal is injected at the cabinet, and filters stop the signal from back tracking into the E-Side.
Not entirely correct.
Some of the current line tests are done from the TAM's in the exchange, for both G.Fast and VDSL2.
Are OpenReach connecting the E-Side on SOGEA lines for giggles?
What do you suppose the purpose of this is without PSTN?
you can't test much about VDSL/G.Fast from the E-Side/Exchange when the data signal is injected at the cabinet, and filters stop the signal from back tracking into the E-Side.
That doesn't prevent tests being carried out from the exchange TAM's kit.
MELT is a DC/narrowband line testing technique that supports the measurements of the electrical line properties at DC, such as resistance, shorts, opens, and capacitance.
MELT operates at DC and at frequencies below the xDSL spectrum, MELT testing can be performed without disrupting broadband services.
Proper testing requires DC coupling of the test circuitry to the line. Not possible on the DSLAM line card because it's AC coupled to the line via a line transformer.
Without sync DSLAM based line testing becomes pretty useless for some tests.
If the DSLAM already does all the VDSL2/G.Fast line tests I ask again why OpenReach are connecting the E-Side to SOGEA connections, on every single SOGEA install.
SOGEA is simply DSL without PSTN.
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@RealAleMadrid Just to check my understanding; is it the case that when the FTTC cabs were put in in your area, the fibre feeds to them were originally put in running all the way direct to that PoP 12 miles away?
I was however talking about a case when this was not so originally; where hypothetically the PoP is at the nearest exchange anyway. But let’s say BT wanted to completely get rid of that exchange ; what would happen then ? A costly rerouting or else just decide not to bother to do it at all, because of the costs involved ?
They picked Head-End/Handover exchanges at the start of the NGA rollout.
Small exchanges that were handling ADSL/PSTN were left as they are.
The Fibre Head-end equipment (OLT/L2 switchas/etc) were installed in the NGA exchanges from day 1, with a future PSTN/DSL switch off in mind.
For those on smaller exchanges their line runs to the PCP/FTTC cabinet, then the E-Side (voice/ADSL) comes from the local small exchange but the fibre runs back to the Head-End.
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Not entirely correct.
Some of the current line tests are done from the TAM's in the exchange, for both G.Fast and VDSL2.
It sounds like they are simply using legacy tests and continue to do so for SOGEA. There is little reason to have an E-Side though if nothing is supplied from the exchange when services are turned off, and it's going to be a very expensive test system if they keep it. Part of the reason PSTN is being retired is the equipment is nearing end of life, but surely its the PSTN line cards that are doing the tests, are they really going to maintain all that equipment just to run a test on the odd telephone from the exchange?
Seems very short sighted if they haven't a plan to test from the DSLAM.
Regards
Phil
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Hi
Philip, I just assumed that fibre comes into say an exchange and then goes out again from there to the FTTC cabs ? And I assumed that you need some dry enclosed place to make the fibre-fibre interconnects or to park switches or L2 routers or whatever ? Where am I going wrong? I realise that I know nothing about the further upstream fibre-side topology of FTTx, upstream of the green cab.
If for example there is a link to another more important ‘new POP’ exchange from a minor local one, are we saying that all FTTC cabs would have new long fibre links to the new POP even though it is much much further away? Apologies for being stupid.
Think this has been answered.
As for a dry space, well no they don't need a dry space. Mostly fibre is jointed and in manholes in the ground which are often wet, damp or full of water. The joints are made to be waterproof and work fine under those conditions.
Because BT FTTP is GPON this works passively. There are no switches or other electrical kit required except at each end, essentially a laser fires down at the exchange and it arrives at the customers premise and vice versa along the fibre.
It is true some other fibre companies use a different type of network with fibre and will require active electrical kit along the route, but not so with Openreach.
Regards
Phil
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@j0hn, PhilipD - It seems that my ignorance of modern post-arrival of FTTC systems is no less enormous than I had anticipated. Many thanks.
The thing about a dry, warm place was an assumption that powered, active kit would possibly be needed, for reasons unknown. I was thinking that aggregation might be required which itself would require mux / demux. But now I think about it, I see that there is no likely need. The individual FTTC cab is perhaps addressed by MAC address (or by the combination of MAC address + VLAN tag?) and then perhaps no need was found to mux the upstream links from multiple FTTC cabs together, because perhaps it costs little more to put two physical fibre links into a duct than one, since arranging the ducts and the labour for blowing the fibre is all that matters in cost terms, and this would be compared to losing the requirement for an otherwise unnecessary active node. Anyway, all wrong thinking on my part, but maybe driven by Highland Think unconsciously perhaps, assuming large distances between nodes with lots of nothingness in between.
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may I ask what may be a daft, or irrelevant question?
When all has come to pass, how will phone numbers be allocated, have any relation to location, be portable etc.? Will directories still exist?
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I heard from one of my colleague, ex-BT, that a rural exchange in our area now has full fibre coverage. Annoyingly I can't remember the name of the exchange, and he's on holiday at the moment. I guess we're all unclear whether the great "copper switch off" implies a commitment to deliver fibre to all premises currently served by copper, so would be interesting to find out more detail.