[HN Gopher] How high speed fiber optic internet cables are made
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How high speed fiber optic internet cables are made
Author : perihelions
Score : 96 points
Date : 2024-08-16 23:22 UTC (2 days ago)
(HTM) web link (www.washingtonpost.com)
(TXT) w3m dump (www.washingtonpost.com)
| malikNF wrote:
| There an old "how things are made" video on yt that explains this
| https://www.youtube.com/watch?v=6CqT4DuAVxs
| Helmut10001 wrote:
| I installed fiber to connect two pv inverters at home, over a
| distance of 120m (to avoid equipotential bonding, through an
| empty conduit underground). On the one hand, fiber is a nightmare
| compared to Cat 7a - you have to handle it carefully, there's a
| pulling grip attachment that's too thick to get through most wall
| holes, and you can't pull too hard or the fiber will stretch
| beyond a certain limit and degrade. On the other hand, our cable
| withstood a lot of force, was bent at 120deg angles, and pulled
| through all kinds of dirt/water without damage. I just wish that
| I could crimp fiber ends myself to avoid all the hassle, but the
| equipment is just too expensive.
|
| It's also interesting that 25m of pre-crimped cable costs almost
| the same as 125m, because the crimping seems to be the expensive
| part, not the cable material.
| dale_glass wrote:
| You can buy some very strong fiber. My home fiber internet
| setup was done with some seriously good stuff. The installer
| left an unneeded chunk and you can't cut that with scissors
| without destroying them. It's some sort of outdoor rated,
| Kevlar reinforced thing.
|
| For LC connectors, the two cables are held with a plastic clip,
| you can remove that to make it fit through smaller holes. After
| that it's much thinner and nicer to work with than Cat7.
| jvanderbot wrote:
| Our ISP installed fiber too late in the year to bury the
| cable, so it just laid on the ground for 7 months until thaw,
| right across our walkway and yard. They weren't even worried
| about it getting damaged.
| jermaustin1 wrote:
| And my ISP had to replace mine multiple times due to lawn
| maintenance guys running it over, neighbors (where the line
| was pulled from) cutting it, etc.
|
| I don't think I'll ever do a fiber install again. If it has
| already been run to the house, great, but otherwise, I'd
| rather not.
| edm0nd wrote:
| Must not have any dogs.
|
| We had fiber installed at our house and our derpy dog
| chewed up the line twice before they were able to bury it.
| Was a good time indeed and thankfully AT&T didn't charge us
| anything to come out and fix it each time.
|
| They only ended up burying it a few inches deep, i was
| surprised and thought it would be deeper.
|
| What surprised me the most is one of the techs telling me
| that ants are one of the most common threats to fiber lines
| outside of them accidently being severed by construction
| crews digging.
| aaronax wrote:
| The most common last-mile fiber assembly I have seen in use
| is called flat-drop. It is flat, and it is optimized for use
| on the drop to the customer premises. There are two
| (fiberglass?) rods and between them runs a loose tube fiber
| bundle with typically 6 fibers in it. Good picture here:
| https://www.novalight.com/Drop-Cable-Fiber-Optic-Flat-
| Toneab...
|
| The fiberglass rods provide excellent crush and cut
| resistance, as well as bend radius control.
| EvanAnderson wrote:
| > For LC connectors, the two cables are held with a plastic
| clip...
|
| Be careful doing that. There are LC connectors that are not
| capable of being split. (I know this because I attempted to
| split one of this type and damaged a fiber assembly at.)
|
| The vast majority of LC connectors I've worked with can be
| split but some cannot.
| msandford wrote:
| I found I was able to get a fiber shear and end maker for less
| than $100 or so.
|
| https://michael.stapelberg.ch/posts/2020-08-09-fiber-link-ho...
|
| Optical Fibre Cleaver SKL-6C Cable Cutting Cutter optical fiber
| CFS-3 stripper Leather wire stripper FTTH tool
| https://a.co/d/6dcvR0l
| whaleofatw2022 wrote:
| > It's also interesting that 25m of pre-crimped cable costs
| almost the same as 125m, because the crimping seems to be the
| expensive part, not the cable material.
|
| When I was doing fiber quoting you would see this with some of
| the bundles, e.x. 72 vs 144. Cost wasn't doubled per foot like
| you'd think, it was a little less.
| wil421 wrote:
| They have special jackets on the fiber with 2 metal wires on
| each side. You would pull the metal wires not the fiber
| directly. Then you would polish the fiber and connect to the
| ont and turn it into an electrical signal (cat6 Ethernet). They
| say the max bend radius is a little larger than a coke can.
| Helmut10001 wrote:
| I think I had a different fiber:
|
| > Fiber SFP (LC) 1310nm, LWL Cable 125m LC-LC 4E OS2, 2x4 LC-
| Connector, Cabletype: U-DQ(ZN)BH
|
| It looks like this [1].
|
| The bend radius was crazy, like 180 degrees curve in a 2 cm
| diameter circle.
|
| [1]: https://www.glasfaserkabel.de/images/product_images/info
| _ima...
| wil421 wrote:
| Yes, that one is good for conduit. I like the bend radius.
| bluedino wrote:
| There are products like armored fiber you can use as well
|
| https://www.fibersavvy.com/collections/armored-fiber-cable?s...
| roshankhan28 wrote:
| i loved it when this type of videos were show on the channel
| history tv 18. those were really great times.
| metadat wrote:
| https://archive.today/C03z0
| chrisMyzel wrote:
| anyone here can say a word or two about ZBLAN fibre optical cable
| created in microgravity environments?
| datadrivenangel wrote:
| My understanding is that they've basically figured out how to
| make regular glass fibers that are basically as good.
| mschuster91 wrote:
| Related question I had for a looong time: how do submarine cable
| layer ships test the cable when they attach a new section? Like,
| these cables need many kilovolts of voltage to supply the inline
| repeaters so you can only power them when the cable is fully
| laid, but how do they verify if the fibers aren't broken
| somewhere along the path?
| jeffrallen wrote:
| They are laid continuously.
|
| But after a repair they are probably tested on deck by re-
| energizing the cable from the landing stations. Although, they
| might behave differently when on deck than on the bottom due to
| the different dielectric constant of water and air.
| hn72774 wrote:
| I once got to do some QA lab systems work at a fiberglass plant.
| Fascinating place.
|
| The molten glass in giant hoppers is gravity fed through very
| expensive rhodium-plated platinum blocks, then spun into a
| plethora of different products and spooled or chopped. Their
| downstream customers would use that as the raw material for end
| products.
|
| I can't read the article because of the paywall though.. not sure
| the nuances between fiber optics and general fiberglass products.
| dekhn wrote:
| If I remember correctly, the first doped fibre manufacturing,
| or maybe the first fibre manufacturing, used an old peening
| drop tower (https://en.wikipedia.org/wiki/Shot_tower) for the
| gravity feed. I guess they are called "drawing towers" now.
| peterpost2 wrote:
| Terrific article, not sure why it makes my laptop crawl to a
| complete halt though!
| mrbluecoat wrote:
| > These glass threads are about the diameter of a human hair, six
| times stronger than titanium and 40,000 times clearer than a
| diamond.
|
| Amazing
| amelius wrote:
| > six times stronger than titanium
|
| But if you bend it too far, it snaps.
| jeffrallen wrote:
| And how they are installed:
| https://www.wired.com/1996/12/ffglass/
| xyst wrote:
| Let's hope this multi billion dollar initiative isn't just
| absorbed by private companies.
|
| I can't find the previous initiative but there was something like
| this in the past where "broadband" internet was to be accessible.
| Miles and miles of wires laid down but most of it wasn't used.
| Benefited the contractors though.
| HelloWolderXYZ wrote:
| Stop posting links to locked behind payment articles.
| s1artibartfast wrote:
| There is no policy against paywalled content and I care more
| about high quality content than the restrictions.
|
| Please don't try to tell others what they can share or read.
| jjcm wrote:
| Naive question - are these fibers pure glass, or some sort of
| composite? Are they flexible because of how thin they are, or is
| it an inherent property of some sort of composite?
|
| The article mentions that these are just silicon dioxide, but my
| brain has trouble connecting the rigidity of glass as I know it
| with the flexibility of fiber.
| choilive wrote:
| "Regular" pure glass fibers would be nearly as flexible. As an
| analogy - the same way that a solid steel rod would be strong,
| but if you make steel fibers that are very thin they can easily
| be shaped and bent. The material properties did not not change,
| just the difference between having a "lot" of something vs very
| little.
|
| In this case, dopants are added to the glass to improve its
| properties as a fiber optic cable and the processing itself is
| important to attain certain properties. But even without those
| added dopants regular silicon dioxide glass would make flexible
| glass fibers.
| ominous_prime wrote:
| Composite fiberglass materials aren't flexible because of their
| composite structure, the layers and resin are there to increase
| strength and stiffness of an otherwise extremely pliable
| material. Think about fiberglass cloth or pink fiberglass
| insulation, glass strands get very flexible as the diameter
| decreases.
| brikelly wrote:
| Absolutely loving the importance and beauty of using gravity in
| this process.
| throw0101d wrote:
| For the last ~decade, NANOG [1] has regularly had a (two hour)
| presentation/tutorial called "Everything You Always Wanted to
| Know About Optical Networking"; most recent one:
|
| * https://www.youtube.com/watch?v=Y-MfLsnqluM
|
| * https://www.youtube.com/results?search_query=nanog+optics
|
| [1]
| https://en.wikipedia.org/wiki/North_American_Network_Operato...
| stefan_ wrote:
| Does someone make, well, low speed fiber? Something to carry Fast
| Ethernet but that can't be susceptible to EMI and doesn't require
| the expensive and power hungry stuff that the real deal does?
| toast0 wrote:
| You're not looking for different fiber really. You're looking
| for different transceivers.
|
| There are fiber ethernet transceivers for all the ethernet
| speeds, I've seem them for 10M, 100M, 1G, 10G, all the Gs.
|
| I feel like SFP (1G) is the sweet spot for cost and
| applicability right now, you can pick up a media coverter with
| one port rj45 and one port sfp for $20 from a reputable
| (consumer) brand, and SFP transcievers aren't too expensive.
| Switched with a bunch of 1g rj45 and one or two sfp are also
| inexpensive new and lots of inexpensive old enterprise gear at
| those speeds too.
|
| For 100M (fast ethernet), I don't know if you'll have many
| options other than old old used enterprise equipment.
| bgnn wrote:
| This!
|
| The biggest cost is in the opto-electric transition parts.
| The mechanical alignment needs to be precise, it needs to
| have a laser, a laser driver (most likely VCSEL), and a
| photodiode with a transimpedance amplifier. It's expensive
| because these parts cannot be integrated with the electronic
| chips easily. They are also bulky.
|
| There are initatives to use crappy alignment optics and
| plastic optical fiber (POF) for short reach Ethernet [1]
| though these aren't commercially available. They don't aim
| for data center or consumer market but automotive and
| aerospace .
|
| [1] https://kd.tech/product/evb9315-sfp-optical-demo/
| duskwuff wrote:
| > For 100M (fast ethernet), I don't know if you'll have many
| options other than old old used enterprise equipment.
|
| You can still buy 100M SFPs [1], but they're about the same
| price as 1Gbps modules, so I'm not sure why you would.
|
| [1]: https://www.fs.com/c/100base-sfp-1668
| LgWoodenBadger wrote:
| You might want to look at media converters.
|
| e.g. https://www.fs.com/products/96396.html?now_cid=1037
|
| I use a pair to isolate my cable-modem from the rest of my
| network, to the extent possible. I once lost a modem and a
| Unifi USG (thankfully only that) to a lightning strike. Now
| with the media converters, hopefully it's only a modem and a
| converter.
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