Corning optical fibre demo

Just thought this video was fairly impressive showing how flexible Corning's optical fibre products are. Not something you usually associate with optical fibre.

Pity nearly all of us without taxpayer subsidised superfast and most with won't really see much benefit. It does look like a good technology especially for MDUs.

Be good to see it tested by a company that actually plan on a scale deployment using it heavily in the field.

So I'm assuming this fibre is "ClearCurve" which was launched in 2007(another, better, demo video - link)? Certainly nothing like the optical fibre I played with as a kid, many moons ago.

Very interesting demonstration.

I remember in the later 1940s that glass-fibre cloth was used as the ribbons decorating particularly the lower tier of wedding cakes, partly availability (war surplus?) and partly that it had a sort of glistening effect, rather like thick solk.

My brother and I were fascinated when we placed off-cuts on the open coal fire; and on retrieving them some minutes later, they would be stiff or solid, the latter then shattering, yet with no obvious burning etc as one would get with ordinary cloth.

I wonder if this could be a fore-warning of future faults with optical fibre, bearing in mind that glass generally is a super-cooled liquid, just waiting to crystallise.

Another use of glass-fibre cloth that I am aware of is the thermal insulation in electric night-storage heaters.

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Back about 1992, a local networking company gave me a demonstration of the various operations needed to employ optical fibre, eg joining two lengths together, polishing the ends for plugs and sockets etc.

Their practice was that generally, they would make up a short connecting cable about 1 foot long (20 cms), polishing the ends etc; and carrying out tests for attenuation, reflections etc, in the workshop, as the connectors were the really critical part of a fibre installation.

The main length of fibre would be run in the customer's premises.

The pre-prepared connector cable would be cut in the middle, the two parts taken to the respective ends of the customer run; and "glass-welded" on.

Then there was the testing of the full cable; but with the assurance that the connectors were almost certainly OK.

Pre-made connectors on leads also known as pigtails are the only way to go.
They even partial test results supplied with each pigtail, splicing the pigtail onto a fibre isn't that hard to do with the right tools, clean enough workspace and sometimes a bit of luck.
I'm envious of the more expensive fibre cable management because the basic stuff leaves a lot to be desired.
Sometimes cable management is half the battle.

In reply to a post by eckiedoo:

I wonder if this could be a fore-warning of future faults with optical fibre, bearing in mind that glass generally is a super-cooled liquid, just waiting to crystallise.

My A-level physics teacher(who was a bright guy) also believed glass was a super-cooled liquid(cathedral windows etc.). Turns out he was wrong - couple of links - link,link.

Edited by Spud2003 (Sat 19-Apr-14 13:51:52)

Glass cloth tapes of various types and formulations is used extensively in the building of very large electrical generators for electrical insulation: I'm talking 100MW+ at 13.8KV+ here.

Pre terminated connections on the optical fibre is how Gigaclear work their FTTP installations.
In effect they are installing a kit which comes in 25m, 50m etc lengths - whatever suits the property.
This in part is why subscribers can equally DIY the installation.
The fibre optic cable of the relevant length comes with the ONT connection point at one end and the conn point to the infrastructure termination point in the road at the other all pre-made.

Evening Spud and the others.

Interesting how much interest my post has given rise to.

Thanks for the two links.

Regarding whether glass is a super-cooled liquid in itself; or simply(?) passes through a super-cooled phase, I note that one of the links is to research work carried out apparently just prior to 2007 and of an esoteric nature, I am not surprised that its results are not yet widely known.

Thundebolt was originally to be a fibre/fiber optic based device interconnection technology (at the time codenamed Light Peak when Intel initially unveiled it) which would place transceivers at each end.

The technology was sadly rejected by the likes of motherboard and other device manufacturers on the basis it was too costly to implement, it was then reworked to use copper and thus resulted in what we now know as Thunderbolt.

Corning's optical USB cables sound like a good idea though but I doubt they will be cheap.

In reply to a post by techguy:

Corning's optical USB cables sound like a good idea though but I doubt they will be cheap.

The Corning 10m USB 3 cable sells for $109 on Amazon.

I should have given a better explanation in my initial post, I posted because the video showed optical fibre being jammed in holes and tied in knots and I didn't recall seeing this before.

So how do Gigaclear prepare the termination of the cable in the ground (pot on customer premises), and how do they connect the supply to each property, to the main cable?

The fibre cable comes into the 'Toby box' ground box
Inside that is an IP64 rated enclosure box - so provided this is closed/sealed up properly it should be totally water resistant inside
The incoming fibre terminates inside that box in a push fit fibre connection.
It looked to me when I saw one like a single mode SC type connector - there are umpteen type.

As to the infrastructure side I'm really not sure. I was rather hoping, like you, that someone else would!
I ought to go round to somewhere where they are digging and try and find out.
I understand it this is not a GPON fibre system unlike BT's FTTP option, this is the gold standard of point to point fibre (same as B4RN) So your fibre runs all the way back from the house to Gigaclear's centrally located village cabinet.
Possibly groups of individual fibre cables from houses are fusion joined to a multi fibre core cable somewhere?

Morning ZOM22

Could you clarify about the "fusion joint"?

Does it mean that each subscriber's fibre connect to an allocated single fibre in a multi-fibre cable back to the exchange, just like a the copper pairs (almost);

or does it mean that all of the subscribers' fibres connect in to one common fibre back to the exchange?

Well I'm treading on thin ice here in that I'm at the very limit of my knowledge.......so here goes to the best of my ability etc on fusion joins, GPON and fibre

A fusion join/splice is where an optical fibre is joined.
It is done in a special machine and even then still requires a knowledgeable operator The ends have to be very clean and cut very flat. The aim is to reduce to a minimum any reflection or distorison at the interface - and is a mark of how good the join is - there may be standards or limits to be met in this respect for an approved join: I've no idea - I'm sure the machine tests the join for loss parameters when it's finished.
Think of it a bit like soldering two copper wires together.

I have been assured by Gigaclear at an open day in person that there is no PON or variations of it in their system. It is point to point with symmetrical operation whether that be 50up/50down or higher speeds if purchased, from the subscriber back to the cabinet.

GPON broadcasts out to multiple groups of residences from a passive unpowered fibre optical splitters situated in the field. This makes it cheaper to install (no power at the splitter) with the end users GPON rated CPE decoding which parts of the broadcast transmission is meant to be for it (it's all encrypted). It has some restrictions with uploads capabilities from the end user due to the nature of its operation.
I suppose the CPE will need to be more complex to do the unscrambling of the data stream.
GPON is just one variant there are others I believe.
I'm also told that a lot of FTTH installations worldwide are GPON.
I'm gather that GPON services cannot by definition be symmetrical - the upload is always lower than the download - but I don't know by how much.

It seems therefore that in Gigaclear's case the property's fibre connection is going individually as a single fibre direct back to the "exchange" which is the actively powered cabinet in the village - it has a 4 hour rated UPS in it.

I really don't know the physical method by which they aggregate all the properties individual fibres back to the village cabinet.
But no - as I understand it it is NOT the case that groups of subscriber fibres are connected to one single common fibre somewhere in the roadside verge and then go as one fibre handling all the group's connections back to the cabinet - which would be GPON.
With Gigaclear EACH house has its own plug to its own fibre at the cabinet - as you said it's like the copper pairs - almost.

What happens of course back from the cabinet to the internet backhaul I've no idea whatsoever. Surely then at this point all the villagers 400 or so connections are aggregated into a few fibres back from there and no doubt contended into sharing out the service between them all
I'd guess the contention and the speed limits restrictions for whichever package an individual subscriber has bought is handled at the village cabinet.
About the only other thing I know is that they are/were using Keymile's milegate racks in the cabinets.

Thanks!

In reply to a post by zom22:

I ought to go round to somewhere where they are digging and try and find out.

Which project?

Slight clarification.
The fibres are Silica, NOT Glass ( which is a mixture of silicates; ) Remembering a project in the 70's they are pretty well immune to most things except a nearby atomic explosion and certainly ideal for eliminating interference say in the confined space of a military aircraft. Perhaps that is why the ban on mobile phones in airliners is relaxed ?

I imagine much of the cost of the USB cable replacement is that it includes an optical Tx/Rx at each end to interface with USB ? I'd love to get hold of one but I suspect that most of the fibre goes into long simple links for BT etc, so the price will be high till they are produced in quantity for offices etc.

I suspect that the main hazard is the RF between the mobile phone and the "base" or "mast" within the aircraft; and that it probably remains that way.

If I remember correctly, mobile/cell phones automatically increase their radiated RF power within limits, to achieve contact (if possible), so further adding to the potential hazard.

However, rather like WiFi on buses, trains etc, I suspect that mobile phones are unlikely to be forced to their maximum permitted output, in the limited volume of an aircraft (A380?); and a few base stations scattered through the the planes

That leaves the aircraft-to-ground link, via satellite, as the other main consideration.

However, it may lead to improvements in tracking aircraft.

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Agreed about the cost of those USB Fibre Links is likely to be in the Optical/Electrical; converters at each end.

Marvellous how small they are.

I wonder if we will be seeing USB 4 (or higher) to cope with the speed potential of the fibre.

In reply to a post by JGO:

Slight clarification.
The fibres are Silica, NOT Glass ( which is a mixture of silicates; )

Actually most fibre used in FTTH is glass traditionally it was a fibre called OS1 which gave losses of 1.0dB/km maximum also called G652D, more recently a newer version came out called OS2 which has lower losses of 0.4dB/km Silica would not typically be pure enough to use on longer distance links back to exchanges for further long haul links.

Zom22 your knowledge is better than you think, the only things I would point out is that most fibre in the UK is either PON or GPON, not P2P certainly up to know. That is why the upload is generally a lot slower that the stated download speed for the links. P2P is becoming more widely adopted at the FTTH role outs increase, if there was not fibre before then many are opting for the P2P although it does cost more to deploy. If fibre is already in the ground then this would be harder to change from PON to P2P as it requires the costly capital works in order to lay more cables on typically developed land or roadways.

Groups such as B4RN and other smaller local enterprises are enjoying the freedom of being able to install their connections as P2P and benefit from the symmetrical U&D speeds, where are areas historically more developed such as towns will most likely always suffer from slower upload speed.

You mentioned another option to PON which uses Passive Splitters is the use of specific wave lengths for sharing fibre links with multiple users,
For example the typical wavelength used for FTTH is 1550nm, but you can use other wavelengths in the same fibre core without interference. Adding more frequencies has a common name of WDM Wavelength Division Multiplexing, and within this there are two options course or dense giving CWDM or DWDM. CDWM uses wavelengths that are more widely spread DWDM uses closer wavelengths. There are various considerations for which to use which I will not go into hear but searching on the above abbreviations will give you some very good information on how it all works and what you need to make it work.

Developments on GPON are WDM PON which uses seperate wavelengths as you mention but the kit is not (yet) common and a lot more expensive at present.

The splitters would then split a seperate wavelength to each premise giving vastly higher potential speeds.

P2P systems are easy to do in small / sparse developments. But imagine the dense areas when you would need 1000s of fibres the fibre management becomes interesting! ( Look at Oldham with 61k premises on samknows!) This is why MDUs often use Metallic tails to the individual units and fibre to the Basement (or sub node) this can reduce the difficulty in the 'exchange' by a factor of 2-400!.

See Irvimic's response, 25th November 2015.

Thanks for this discussion guys, it's bringing back memories of my own work with Marconi in the late 90s when we were working on WDM technologies. At the time most solutions for the mux and demux involved an optical-electrical-optical switch which was inefficient and needed power. We were working on a fully optical system which I presume is now a reality?

In reply to a post by andyhurley:

We were working on a fully optical system which I presume is now a reality?

I have a vague recollection of the hardware guys working next to us softies getting a demo of a pure optical switch working in the late eighties. That was Plessey/GPT, so I guess a precursor to Marconi. They were pretty pleased with themselves...

Yeah, the reports I heard were all rather self-important too. I was actually working for Nokia on software for the switches (precursors to the modern DSLAMs I guess - a few optical connections and lots of POTS designed to fit in exchange racks or cabinets). Marconi bought us and we were subjected to the rhetoric of WDM being the future, ironic that Marconi went bust a few months later...

In reply to a post by Irvimic:

If fibre is already in the ground then this would be harder to change from PON to P2P as it requires the costly capital works in order to lay more cables on typically developed land or roadways.

Ironically, that is probably the position we are *already* in, here in the UK.

The biggest saving offered by a PON over PtP is in the amount of fibre at the higher levels of the tree - between exchange and splitter.

The mostly-FTTC rollout has come with a rollout of the first layer of a future fibre access network - the fibre spines running from exchanges to chains of aggregation nodes. These will already, I reckon, be dimensioned more appropriately for PONs than for PtP.

Even though the current FTTC cabinets use PtP fibre, g.fast seems to be heading towards GPON and 10G-PON uplinks. I don't know if that is because it makes it easy to trial, to start with, or because that is the best long-term business case.