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Telephone Line Rural Outside Plant
- ale42 2y agoI love landline phones (when they work right, which is not the case everythere) because usually they have better sound quality than mobile (which can be good-to-horrible depending on network quality) and almost zero latency. But it's time to switch to fiber optics!
- Bluestein 2y agoTotally.- PS. But, can you do fence-wire comms with fiber? :)
- schiffern 2y agoWe often talk of developing nations "leapfrogging" landlines and going straight to mobile, but they're also going straight to fiber. It would be fascinating to see this same type of breakdown for rural fiber infrastructure. One obvious difference is that fiber can't self-power a phone, but with ubiquitous mobile phones/solar panels/powerbanks that doesn't strike me as a huge show-stopper. Thanks OP, great post and content. Now I'll go through the world with new eyes! EDIT: found the fiber page http://cityinfrastructure.com/single.php?t=Fibre%20Optic%20Cables&d=FibreRun http://cityinfrastructure.com/single.php?t=Fibre%20Optic%20C...
- Bluestein 2y agoInteresting, the "straight-to-fiber" leapfrogging. Was not aware. Makes sense.- I'd be interested to know - qua infra - what their power grids are looking like ...
- detourdog 2y agoEstonia when it left the Soviet Union was offered a used phone system from a country that wanted to upgrade. Estonia decided to build new. https://theconversation.com/estonia-is-a-digital-republic-what-that-means-and-why-it-may-be-everyones-future-145485 https://theconversation.com/estonia-is-a-digital-republic-wh...
- Bluestein 2y agoSmart move.- PS. Also, interesting that there - apparently - is a "second hand" market for used phone systems. As in, wholesale.-
- detourdog 2y agoObviously excepting the cruelty I love the modern world. I marvel at the organization and patterns. The Soviet Union was suffering some food crisis in the 90’s. One morning the news was discussing Clinton granting food aid to them. That same morning as my subway crossed by the Dominoe sugar factory there was already a Russian ship docked. That was such a strange cause and effect moment for me.
- johannes1234321 2y agoIt's interesting with East Germany - after German reunification it was covered with fiber. However then DSL became the standard way of going online in Germany, while that doesn't work on fiberand with only few to no consumer priced offerings for FTTH many areas were left out from "fast" Internet for a while, while having the, in theory, superior net.
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- mschuster91 2y ago> I love landline phones (when they work right, which is not the case everythere) because usually they have better sound quality than mobile (which can be good-to-horrible depending on network quality) and almost zero latency. That was the old landlines, of actual POTS, era. Back then, there was a direct electrical circuit literally switched using relays between both participants in a call, with only amplifiers, switches and power sources in between. More modern systems used banks of relays, and then it all went downhill quality-wise. First, the telco core systems were replaced with digital trunks that had ADCs on both ends of a call in the regional distribution center, and consumers were switched over to ISDN for telephony. Then, the analog/ISDN frontends moved to the curb side where ADSL, VDSL and nowadays G.fast frontends were added to the mix, which were connected to the telco network using fiber. Then, analog and ISDN were shut down, with voice phone calls being migrated to VoIP. And nowadays, it's the full evolution with GPON - on the telco side, there's only fibers and a single TX/RX pair of transmission modules serving up to 64 customers. What used to require a whole multi-story building can now be done in the space of a better-quality shed. And the analog frontend is only at the CPE, if there is an analog frontend present at all and it's not VoIP softphones or DECT.
- Dibby053 2y agoMy new ISP took this to another level: if you transfer your landline phone number they send you a voice-only SIM card and a 4G router into which you're supposed to plug your landline. Calls to the landline number are redirected to the number in the SIM (with a significant delay). I wonder why they did it this way instead of implementing VoIP, especially since the all-in-one GPON/Wi-Fi router already has a landline port.
- actionfromafar 2y agoMaybe requirements on availability?
- dfc 2y agoWhat ISP do you use?
- ale42 2y ago
- razakel 2y agoIt was time to switch to fiber 50 bloody years ago.
- marcus0x62 2y ago> But it's time to switch to fiber optics! The PSTN has been hybrid fiber/copper for decades. The vast majority of inter-CO traffic is carried on fiber optic lines. Many POTS lines are carried on fiber optic carriers from the central office to a subscriber loop carrier or similar device and then only travel a short distance to the subscriber premises on copper lines.
- zabzonk 2y agoin the UK it is typically fibre to the box on the street, and then copper from that to the house. providers would love you to subscribe to fibre to the house (so they can charge you exorbitant prices for it), but really YAGNI for most people at least in my experience.
- sgt101 2y agoThat used to be the case - but it's rapidly becoming standard to be directly connected to fibre. I believe that something like 60% of UK premises have a fibre connection available and I expect that all the providers will push folks off copper as fast as they can. Because copper is a pain in the arse compared to fibre (for the provider). For the consumer copper has one key positive that fibre just doesn't - it works in a power cut.
- lxgr 2y agoIn Germany, in particular in the former East, fiber development inadvertently got in the way of fast home Internet access for many years: Many regions were built out with (at the time of the German reunification) state-of-the-art hybrid fiber/copper systems, with fiber extending even beyond the central office. Unfortunately, the technology used is incompatible with DSL, the access technology of choice of the former incumbent operator, so any landline deployed using it was ineligible for anything faster than dialup until they either built out a copper link to the central office, or upgraded the existing fiber to GPON (which didn't happen until very recently).
- ale42 2y ago> The PSTN has been hybrid fiber/copper for decades. Definitely, I was mainly thinking about those thousands of lines coming out from the CO...
- linsomniac 2y agoIf you think POTS sounds good, you should try ISDN, it'll knock your socks off! Back in the mid-90s I got ISDN BRI (2x64Kbps channel) service in to replace analog modem service. It would connect in well under a second, and while connected at 128K we could receive a phone call (dropping one of the channels, so having voice plus 64K data), and the phone calls sounded quite good. It used to be that for recording remote interviews or even I believe just general voice recording like audio books, the media companies would have you come into a location that had ISDN, and if you were a real big timer you might have ISDN in your home studio. That was back in the day when they gave a crap, then the pandemic came along and the media companies seemed to be happy throwing any crappy video chat up for broadcast, not matter how echoy the room you're in or how many drop-outs. WRT fiber optics, we are just now starting to see Q.com (Century Link) deploying fiber to the neighborhoods. Up in Canada in a similar sized city they deployed fiber back in 2000, but in the states QWest wouldn't do it because, I've been told, it would open up allowing CLECs to put DSL equipment in neighborhoods, and let them cherry-pick neighborhoods to offer service in. Finally a few years ago the city stepped in a ran fiber to every house, which honestly is a better option IMHO.
- shepherdjerred 2y agoI've had Quantum Fiber in Seattle for a year or two now. It's fantastic! Symmetrical upload/download, no data cap, 1gbps, and I pay something like $75/mo. I was paying $100/mo to Comcast for the same thing, though I had 1.2gbps down/35mbps up.
- wrycoder 2y agoIs your endpoint routable? Is the IP fixed or dynamic?
- volf_ 2y agoYes. Dynamic as the IP is renewed everytime your device resets
- linsomniac 2y ago
- ape4 2y agoNaive question: Was fiber always digital? I could imagine varying the intensity of the a laser signal to send sound.
- zabzonk 2y agobut ... why?
- ale42 2y agoSimpler and cheaper electronics, probably.
- declan_roberts 2y agoI can't imagine that subtle light intensity would survive the various light amplifiers used along the way.
- ooterness 2y agoRadio-frequency over fiber (RFoF) signals are usually analog. By intensity-modulating the laser, it's relatively easy to convert a GHz-wide analog signal from electrical to optical and back. https://en.wikipedia.org/wiki/Radio_over_fiber https://en.wikipedia.org/wiki/Radio_over_fiber https://www.rp-photonics.com/radio_and_microwave_over_fiber.html https://www.rp-photonics.com/radio_and_microwave_over_fiber....
- Dead_Lemon 2y agoI've been enjoying the videos of 'Look Mum No Computer', building his own 60's based, electromechanical telephone exchange, is his Museum of everything else. https://www.youtube.com/watch?v=tK1lH8pjXTo https://www.youtube.com/watch?v=tK1lH8pjXTo His second channel has some more dedicated content on telephone systems, https://www.youtube.com/playlist?list=PLKnS0AB2CTN_eu8k8rgaOW0PWFH2Qv9U https://www.youtube.com/playlist?list=PLKnS0AB2CTN_eu8k8rgaO... He has spent a fair amount of time building it out, from initially receiving his first exchanging and getting it to work, and adding more to it It fun just to watch how the system selects lines and routes around the exchange. Other interesting things, like how the dial and engaged tones are generated, and how prerecorded messages are played back to a number that is no longer in service, something like, 'This number no longer exists, please try again'
- hyperbolablabla 2y agoSo phreaking cool
- jagged-chisel 2y agoiswydt
- volf_ 2y agoAlso check out https://www.youtube.com/@ConnectionsMuseum https://www.youtube.com/@ConnectionsMuseum The channel is about the fully functional Central Office turned Museum in Seattle
- hiatus 2y agoI don't know if it's just me but the playlist link you shared just redirects to the homepage.
- Dead_Lemon 2y agoI see its doing the same for me now too. I didn't know they expired. Here is the channel, https://www.youtube.com/@THISMUSEUMISNOTOBSOLETE https://www.youtube.com/@THISMUSEUMISNOTOBSOLETE
- Jordan_Pelt 2y agoI really want to see the insides of those buildings.
- volf_ 2y agohttps://www.youtube.com/@ConnectionsMuseum https://www.youtube.com/@ConnectionsMuseum There's a fully functional system deployed in Seattle as a Museum
- mjcl 2y agoThere's some videos on the AT&T Tech Channel on YouTube that show inside the CO, like this one for the "Speedy cutover service": https://www.youtube.com/watch?v=saRir95iIWk https://www.youtube.com/watch?v=saRir95iIWk
- strivingtobe 2y agoTIL the origin of the term "cutover" for IT migrations. Fascinating!
- Bluestein 2y agoI really do hope y'all excuse my ignorance, but ... ... what part of the "switchover" process is this? That is to say ... ... I get that you have to cut to switch over but ... what would come next? Does the new system get spliced in? Is it already wired - pending just the cut? (Thus the speed with which it is done) ...
- icehawk 2y agothe new system is already spliced in, but is electrically isolated. the old system can't be isolated like that so they have to physically cut the wires to it before they electrically connect the new system, which is the switch throw at the end of the cutover.
- Bluestein 2y agoMakes sense. Thanks!
- WarOnPrivacy 2y agoNow we get to a really interesting part. As you drive along rural roads, you'll see what appear to be paint cans, each with a this cable coming out the top. As you might have guessed, these therefore are not paint cans, but are the enclosures for the loading coils. If there is a 600-pair cable, then you need 600 loading coils (these look something like little spools of thread), and you need to attach each to the feeder cable. I hadn't seen that config before. (looong-time infra rubbernecker). I assume I've seen variants but am not recalling what they look like.
- kibwen 2y ago> Here's a close-up of the 1,200 pair cable. Terminating that must be a lot of fun. Please tell me they have some clever device that makes this task easier.
- paradox460 2y agoThey had splice tools, but you were still threading cables to each other by hand. The model train club I used to be a member of was full of old telephone guys, and they'd share old stories
- sgt101 2y agoYeah - there are colour codes you can use to find the pair that you want to connect, they are arranged in a mystical system of binders. It's like a map.
- zikduruqe 2y agoBack in my telephone days, I used to use this to remember my pair colors. We Rape Beautiful Young Virgins (for the White Red Black Yellow Violet) and Big Old Gob of Bull Shit (Blue Orange Green Brown Slate). There were other mnemonics other people used. https://en.wikipedia.org/wiki/25-pair_color_code https://en.wikipedia.org/wiki/25-pair_color_code Back in my younger days when I ran a switching office, I used to rip a few bong hits, put on some music and wire DSX panels on the weekends and just zen out. It was therapeutic.
- sgt101 2y agouhmmm ok....
- ssl-3 2y agoThe way to terminate a 1200-pair cable is the same as eating an elephant: One bite at a time. Historically (and in the US, at least), telephone wire has been organized into chunks of 25 pairs each, with each pair of wires having a unique color code. And every 25 pair cable in a given system has the same set of wire colors. And these 25-pair chunks are easy to terminate on (say) a 66 punch-down block. It takes some time to learn how to get good at it, but not as much time as one might think. Those 25-pair chunks are organized into 5 different body colors, each with 5 different pair colors. We're all familiar with the colors of 4-pair cat5 and friends; that's just the first 4 pairs of wire of a 25-pair chunk. (We can tell that they're the first 4 pairs because they all have the color white in common with eachother.) So, the order for a 25-pair cable is this: First, the white pairs: Blue, Orange, Green, Brown, Slate. Then the red pairs: Blue, Orange, Green, Brown, Slate. Then the black pairs: Blue, Orange, Green, Brown, Slate. Then the yellow pairs: Blue, Orange, Green, Brown, Slate. Then the violet pairs: Blue, Orange, Green, Brown, Slate. Done. A 25 pair cable is terminated. --- Larger cable are also organized into 25-pair chunks. The colors of the binder strings wrapped around each 25-pair chunk identify it. This works for cables with up to 600 pairs. --- 1200-pair cable just consists of two 600-pair groups, with each group wrapped in its own colored binder --- So to begin terminating a 1200-pair cable, first you identify the first group of 600, based on the color of outermost binding wrap. Now the 1200-pair problem is only a 600-pair problem. Inside of that group of 600, find the first chunk of 25 (the white-blue one). Now your 600-pair problem is only a 25-pair problem, and terminating 25 pairs is easy. So terminate all 25 pairs, and then move onto the next chunk of 25 (white-orange). Keep doing this until you've worked through all 24 chunks of 25 pairs in that 600-pair group. And then just do it again for the other 600 pairs. []: http://cityinfrastructure.com/OutsidePlant/Webfiles/colorcodes.pdf http://cityinfrastructure.com/OutsidePlant/Webfiles/colorcod...
- paradox460 2y agoAs a kid in Los Alamos, the mesa I lived on was far enough from the central office[1] that it had some loading coils between us and them. This meant that we couldn't get DSL on that mesa. The mesa across the way didn't have the loading coils, and thus was able to get DSL. I remember the jealousy of my friend being able to download DOOM WADs in a couple of seconds, while I had to schedule them, or convince my dad to download them on the much faster connection at LANL. Eventually we managed to get either an ISDN line or a T1 line, I cannot remember which, but shortly thereafter Cable internet became available, and rendered the whole problem moot. [1] Los Alamos had one central office, with a big microwave relay in the top of it: https://i.imgur.com/Lcfj9oA.jpeg https://i.imgur.com/Lcfj9oA.jpeg
- SoftTalker 2y agoI didn't know that these cables are all pressurized with air to keep leaks out (and to dry out any leaks that do happen). To me, that was honestly the most interesting thing in the article.
- russfink 2y agoA lesson in how not to use parentheses in technical writing.
- Abismith 2y ago[dead]
- JSDevOps 2y agoCool read