[HN Gopher] 10mbps over 1km on a single pair of wires
       ___________________________________________________________________
        
       10mbps over 1km on a single pair of wires
        
       Author : yosheli123
       Score  : 242 points
       Date   : 2022-06-22 11:21 UTC (11 hours ago)
        
 (HTM) web link (botblox.io)
 (TXT) w3m dump (botblox.io)
        
       | vicek22 wrote:
       | - 1km of fiber optic cable - https://www.amazon.com/Jeirdus-
       | Launch-Singlemode-Measuring-O... - 1Gb modem -
       | https://www.amazon.com/TP-Link-Ethernet-Converter-Multi-Mode...
       | 
       | The price for two modems and the cable is just under $120
        
         | terom wrote:
         | A 1km reel of unsheathed 9/125um single fiber strand would last
         | maybe about one minute during installation before it snapped.
        
         | Zenst wrote:
         | 1KM of fiber cable for $60 seems crazy cheap when you contrast
         | it with 3D printer filement. More so as I'd of thought the
         | former be more expensive to manufacture.
        
           | klodolph wrote:
           | There aren't that many types of fiber optic cable, the actual
           | cable diameter is extremely small (single mode might have 9um
           | core), and the product is used in large quantities by price-
           | sensitive, sophisticated consumers doing large-scale capital
           | investments. Ethernet cable is also very cheap.
           | 
           | 3D filament is a consumable, like paper!
        
           | inetknght wrote:
           | Fiber is generally laid just once. But the filament is a
           | recurring cost to consumers so it provides more value to
           | businesses ... and therefore more opportunity for a higher
           | demand and higher price.
        
             | Zenst wrote:
             | Does seem very much that the whole 3D filement market just
             | needs one disruptive supplier. Which often happens when you
             | have high-margin consumables markets. Which with the ink
             | printer market saw makes of the printers introduce DRM into
             | the consumables - something I don't see happing with 3D
             | filement though, so could be interesting.
             | 
             | That all said, I see that there are products that can
             | convert your plastic bottles into 3D printer filement -
             | https://3devo.wpmudev.host/filament-makers/
        
         | ape4 wrote:
         | You can also buy 50km on that page! But the fiber is raw
         | (unprotected) so I would think that its not usable to run
         | outdoors?
        
         | Youden wrote:
         | You linked unterminated single-mode fiber and a dual-fiber
         | multi-mode media converter, you can't actually use these
         | together.
         | 
         | You need something more like this:
         | 
         | - Terminated single-mode fiber:
         | https://www.fs.com/products/74355.html?attribute=255&id=3029...
         | 
         | - 2x SFP transceivers: https://www.fs.com/products/75335.html
         | 
         | - 2x media converters (or NICs):
         | https://www.fs.com/products/96396.html
         | 
         | The price is over $200.
        
           | nousermane wrote:
           | Wouldn't cost of burying that cable be like 50x of that
           | anyway?
        
             | sethhochberg wrote:
             | These solutions for things like IP-over-copper-pair are
             | typically designed for situations where you already have
             | the cable buried or strung on poles or whatever - so the
             | choice isn't whether to lay new copper or lay new fiber at
             | roughly equal expense, its really whether to use the
             | existing copper or lay the new fiber at much greater
             | expense
        
               | jagger27 wrote:
               | Thank you, this wasn't clicking for me until I read this.
               | Of course there are countless places with a dead phone
               | line hanging between them.
        
               | hinkley wrote:
               | Or a fat old conduit that you can run a new wire
               | through...
        
               | jagger27 wrote:
               | I can't imagine a scenario where you already have a 1km
               | long conduit that doesn't already have copper or fibre in
               | it. Why would you choose to push a kilometre of brand new
               | copper twisted pair line down an existing conduit just to
               | squeeze 10 Mbps out of it? The hard part is already done
               | and fibre equipment is pretty cheap.
               | 
               | If the conduit already has a phone line in it that isn't
               | being used, sure.
        
           | zakki wrote:
           | If you look closely in the parent's fiber product photo (last
           | picture), the seller providing the connector for free.
        
         | yosheli123 wrote:
         | Yeah, I think there's other considerations like power, overall
         | size, input voltage supply, ease of maintenance etc.
         | 
         | If it's purely down to cost then I don't these modules would
         | compete
        
         | xhrpost wrote:
         | Nitpick, I don't think you're going to just run bare fiber
         | outdoors, not even indoors. You would need to first run your
         | own ducting/conduit and then have the equipment to pressure
         | force the raw line through the shielding. So, much more
         | expensive. But you can get outdoor rated cable with moisture
         | absorbing gel for not too much I believe (struggling to find a
         | price). Some even come with wire-mesh already attached in the
         | event you have to hang it between elevated positions (like
         | telephone poles). But you would need all of that for a copper
         | run outdoors as well so it doesn't change your point.
         | 
         | Back to your point, fiber came to my mind as well. Why bother
         | running CAT5/6 when you can just run fiber? Maybe its meant for
         | existing infrastructure? But if that's the case, what was
         | utilizing that infra before? Is it just in cases where you
         | happen to have phone lines running between buildings?
        
           | snickmy wrote:
           | what does 'pressure force the raw line through the shielding'
           | means ?
        
       | jacknews wrote:
       | SPE (Single-Pair Ethernet) is going to be a big deal, IMHO, and I
       | would view this as a 'development board' for learning, though
       | perhaps it also makes economic sense as an actual solution in
       | some situations.
       | 
       | The other killer feature of SPE (apart from in-theory cheaper
       | cabling) is PoDL (Power over data line). Does this board do that?
        
         | ginko wrote:
         | What's the advantage of SPE compared to regular ethernet? That
         | it's cheaper?
        
           | quickthrower2 wrote:
           | Well my house has electricity sockets but no ethernet
           | sockets, so it would be less expensive than getting those
           | installed. If I could stomach sub-wifi speeds.
        
             | phonon wrote:
             | Have you tried G.hn powerline to Ethernet?
        
             | 2000UltraDeluxe wrote:
             | Why not use the power lines?
             | https://en.wikipedia.org/wiki/HomePlug
        
             | plasticchris wrote:
             | Just get a decent mesh WiFi, should get around 600mbps or
             | better, it's cheaper too.
        
             | NegativeLatency wrote:
             | You can do your own Ethernet, it's especially easy if
             | you're just running a wire or two for an extra AP or
             | something with premade cables
        
           | jacknews wrote:
           | Cheaper cabling, at least in theory, but I'm not sure
           | ethernet (for data) is the right comparison.
           | 
           | IMHO, in the near future, data-intensive connections will
           | move to wifi 6/7/etc, or to fiber. Copper will be for
           | providing data _and_ power. IMHO, it makes more sense to
           | compare SPE to current PoE networks /devices, powered wifi
           | devices, CAN bus, rs485/modbus, and other wired IoT and
           | industrial networks.
        
           | yosheli123 wrote:
           | Smaller, lower power, more reliable + a somewhat open spec
           | being developed around it (unlike things like homeplug which
           | are kinda murky). Generally it's the same people who
           | developed the ethernet spec that are developing single pair
           | ethernet, so it's designed to play nicely with it.
        
       | Ahwd wrote:
        
       | PeterPumpkin45 wrote:
        
       | worldofmatthew wrote:
       | Something like this is what this is competing with;
       | https://www.ebay.co.uk/itm/314029740243
       | 
       | In the US, you will be able to get these cheaper than the product
       | on Botblox and with better performance (both products require a
       | pair). "20/12Mbps over a long distance of 1.4km"
       | 
       | The author might be more competitive when he managers to go
       | $100/pair (which he mentioned in another post he plans to by Apr
       | 2023).
        
         | varjag wrote:
         | DSL isn't it. Not anywhere as easy to embed into products as 2
         | wire Ethernet, and you miss PoE option.
        
           | [deleted]
        
           | worldofmatthew wrote:
           | Not a hard problem to solve as both are twisted pair and POE
           | injectors are a extremely cheap.
        
             | yosheli123 wrote:
             | tbh I don't think I'm really ever going to compete with the
             | mass volume stuff on DSL. I think this is more for
             | applications where space is the key motivator, rather than
             | cost.
        
         | yosheli123 wrote:
         | Yeah I'm really targeting directly embedded applications that
         | will want single pair ethernet. Robot tethers and things like
         | that.
         | 
         | $200 a pair is definitely possible. $100 a pair is probably
         | possible in a year or so, I just can't place orders for the
         | chips in bulk because of the chip shortage so everything is
         | inflated.
        
       | [deleted]
        
       | superkuh wrote:
       | If you use a surface wave transmission line with RF launcher
       | cones on the ends you can send gigabits over a _single_ 28 awg
       | copper wire at very low loss from 100 MHz to ~10 GHz. The only
       | problem is that the line has to be suspended and away from
       | conductors.
        
         | madengr wrote:
        
         | superkuh wrote:
         | madengr responded with a completely on topic link to a surface
         | wave transmission line start-up. But it looks like that
         | comment, and 2/3 of their other on-topic posts are getting
         | grayed out [dead]. I don't think they know.
         | 
         | madngr: your account my be shadowbanned and only viewable by
         | those like me that show dead posts.
        
       | gtirloni wrote:
       | Why are you mostly ignoring fiber comments in this thread? It
       | seems like a no-brainer.
        
         | withinboredom wrote:
         | There are lots of reasons to choose something other than fiber,
         | this isn't/shouldn't be a discussion of why you, or anyone
         | else, would choose fiber instead of this product. It's pretty
         | obvious that there is fiber in the world and saying "but
         | there's fiber!" isn't very constructive.
         | 
         | Some off the top of my head reasons why I wouldn't choose
         | fiber:
         | 
         | - runs that require turning very sharply, beyond what fiber can
         | handle.
         | 
         | - applications where the cable can undergo sheering forces
         | causing sharp bends or damage.
         | 
         | - applications where the cabling already exists.
         | 
         | - in cases where the cabling is already owned thus this becomes
         | quite cheap.
        
         | kjs3 wrote:
         | No one is obligated to respond to every "you didn't do it the
         | way _I_ would have done it " comment.
        
       | neilalexander wrote:
       | Unless you absolutely need to go 1 kilometre specifically, what
       | are the advantages to this over using G.hn? On shorter runs G.hn
       | will go anything up to 1.8Gbps and will still manage well over
       | 100Mbps on anything up to about 700-800 metres. Even
       | better/further with coaxial instead of twisted pair.
       | 
       | I've been using a pair of GIGA Copper G4201TMs to take advantage
       | of twisted pair wiring at home rather than having to rip it out
       | and it also appears more cost-effective:
       | https://www.gigacopper.net/web/en/ghn_faq_en.html
        
       | jimmyswimmy wrote:
       | Actually need something like this, but I need to be able to
       | program the microcontroller for my own uses (to use it to convert
       | and transfer sensor data). Is the firmware source code available?
        
       | zajio1am wrote:
       | 10 mbps or 10 Mbps? That is 9 orders of magnitude difference.
        
         | memorable wrote:
         | The website says 10Mbps. OP seems to not pay attention to that.
        
       | ladyattis wrote:
       | I wonder if keeping the wires on a spool is what allows the speed
       | to be the range of 10mbps? I only ask because I know at least for
       | radio signals there's capacitive coupling between wires which
       | some signal leakage will happen. But I assume as long as the
       | signals are differential as in current flow between the two wires
       | are in opposition which should in theory be fine, so common mode
       | signals ought not to leak over.
        
       | gandalfian wrote:
       | I'm 1km of copper to green box, then fibre rest of way to
       | telephone exchange. VDSL 40mb down and 6mbs up. That's on a
       | 1980's buried copper cable.
        
         | unwind wrote:
         | Neat, but is that copper a single pair?
        
           | midasuni wrote:
           | Yes that's how the traditional phone system works, single
           | pair from your house back to the exchange (via a jumper block
           | in a cabinet nearby). Modern DSL equipment can get upto
           | 50mbit aggregate speed over 1km of traditional phone wire (so
           | 40/10, or 30/20 or however you would want to set it up)
           | 
           | Condition of the wire will effect it of course, aluminium
           | wire, ground conditions, cross talk etc could lower your
           | speed.
        
             | jandrese wrote:
             | I think the difference with this product is the
             | transceivers are $150 each and you don't need anything else
             | to use them except for a couple of power supplies.
             | 
             | I do find it interesting that their box diagram claims a
             | 2km range.
        
           | anderiv wrote:
           | DSL uses a single pair, yes.
        
       | geozimm wrote:
       | All these things are related. Back in the 1990s I worked with
       | others to develop DSL technologies (ADSL, HDSL, VDSL) for telcos.
       | Why not fiber, some ask? oh, fiber materials may be sand, but
       | installed fiber is sand, energy, and labor. Installation costs
       | trump everything - use what you have for the physical medium.
       | 
       | While we (PairGain) also made point-to-point private links, it
       | was clear then, and even moreso now that most DSL involves a
       | service provider managing the network - with specialized skills,
       | practices and setup.
       | 
       | In the 2010's I was spending time with the Ethernet folks, and in
       | particular industrial folks with large plants. I ended up
       | chairing IEEE Std 802.3cg which developed the 10 Mb/s 1km
       | technology. Not really a speed increase - more an application
       | refocus. As the networking world developed, many realized that
       | converging networks above the physical layer added network
       | complexity and therefore setup and ongoing operating costs... So
       | we now also have SPE - pure Ethernet at DSL-like distances...
       | 
       | Similar tech with different use models, enabling connectivity for
       | whatever...
       | 
       | I'm not Al Gore - I won't claim to have invented the internet. I
       | just an engineer who happened to have a hand in both of these
       | technologies, and am still pleased to see that people use them.
        
         | cm2187 wrote:
         | Fiber doesn't conduct electricity, a wire does. I remember
         | reading somewhere to be careful with running a wire over any
         | long distance between two houses that are not connected to the
         | grid with the same meter. Something to do with phase or
         | different potential, can't remember, but the point was it could
         | fry your equipment. Fiber sounds a lot safer to me.
        
           | midasuni wrote:
           | The biggest problem is lightning strikes hitting the cable.
           | The phase wouldn't matter - and even different earthing
           | wouldn't matter as long as you only connect any shield at one
           | end.
           | 
           | But fibre is so much more versatile if you're running new
           | cables (unless you want to run power)
        
             | repiret wrote:
             | Last summer the local cable company replaced all their
             | cables in town in order to begin offering digital cable and
             | internet service. I was flabbergasted that they they spent
             | all that money on linemen but still ran coax rather than
             | fiber. As far as I can tell talking to their linemen, its
             | not even FTTN, just FTT-central-office.
             | 
             | Assuming its not run by morons, which I'll accept is a bit
             | of a stretch for a cable company, there must be some other
             | reason to not run fiber for new installations.
        
               | Aloha wrote:
               | Cost and Fragility.
               | 
               | You can push around 1GHz of bandwidth on the normal
               | hardline-feed line with taps system cable uses, each node
               | is designed to pass by a certain number of households.
               | 
               | Coax is.. cheap, forgiving, easy to terminate, and
               | inexpensive to replace - Fiber is more expensive,
               | unforgiving, and much harder to terminate.
        
               | rodgerd wrote:
               | https://www.chorus.co.nz/tools-support/broadband-
               | tools/broad...
               | 
               | New Zealand has fibre to the home for the majority of a
               | country the side of the eastern seaboard of the US, with
               | only 5 million people, and a lower per-capita GDP.
               | 
               | It's doable. It's just a question of wanting to.
        
               | Aloha wrote:
               | Its just not as efficient, you can deliver similar
               | classes of service by HFC networks.
        
               | GreyStache wrote:
               | Regarding the termination: our local fiber provider
               | handles the termination with some optical precision
               | connector (forgot the name). Both to the sunken-in-
               | sidewalk multiplexer and in the home to the optical
               | termination point (both gpon). So for mass deployments
               | fiber connections do not require fibre welds are not
               | required.
               | 
               | I have to see it play out in practice and I'm not a fan
               | of the idea that one telco controls controls (ie stifles
               | competition) in a gpon scenario. The conduit has recently
               | been placed in our street, so "soon"...
        
               | Aloha wrote:
               | I'm still a fan for cost reasons of FTTN, because I think
               | with Coax in the last mile, you can deliver fantastic
               | performance, so long as you're not also trying to
               | delivery video too.
               | 
               | Furthermore if you actually run Coax in duct for buried
               | circuits, its easy to replace with fiber later.
        
               | bayindirh wrote:
               | Our telco converted all its infra to FTTN via fiber. So,
               | I've actually have fiber connection up to the front of my
               | building, then it's terminated and distributed via VDSL
               | to the street.
               | 
               | I have a 50/8 mbps connection at home and, it gives all
               | the performance it can give. The telco keeps the speeds a
               | bit higher to handle VDSL overhead, so we have a real
               | 50/8 mbps IP connection at premises.
               | 
               | I'd rather not rewire my home and use existing equipment
               | (which can handle 350mpbs), rather than bringing in
               | fragile fiber into the home.
        
               | xenadu02 wrote:
               | This sounds like post-hoc rationalization.
               | 
               | I have Sonic fiber in SF. 1Gbps symmetric, over a
               | "fragile fiber" run directly into my home. It works quite
               | well. The drop cable is pre-made in standard lengths with
               | weatherproof connectors. The glass is embedded in a
               | large-ish diameter substrate that resists sharp bends
               | naturally so the installers don't need to take special
               | care to prevent losses, just don't try to force the cable
               | to bend beyond what it wants to do (very different from
               | your standard fiber patch cables in a switch room). It is
               | robust enough you could cable staple it to a wall without
               | issue. Terminates in a tiny ONT that gives me Ethernet on
               | my side.
               | 
               | They're deploying 10Gbps for all new installs and I'm
               | eagerly awaiting my upgrade. No change to the fiber
               | itself are required, just swapping equipment on both
               | ends. This same fiber can do 100Gbps in the future if the
               | need arises, possibly more. No coax plant can come close.
               | The fact that an independent ISP can do this for
               | $40/month and make money at it proves the economics.
               | 
               | There is no reason not to run fiber unless you're more
               | focused on rent extraction than investing in your
               | business... at least in suburbs and cities. (See ATT's
               | public comments and focus on milking wireless while dis-
               | investing in physical plant as an example of goosing
               | profits because they don't face real competition in most
               | of their service area).
        
             | madaxe_again wrote:
             | Then you just install a lightning arrestor on your comms
             | circuit - I have a mast way up the hill to provide our
             | connectivity here, and use one on the Ethernet line down to
             | prevent issues (like a house fire) from a strike.
        
               | dboreham wrote:
               | There's really no "just" concerning lightning protection.
               | You can just add some protection, to code or above, but
               | it may not work. Nature can be unforgiving.
        
               | Aloha wrote:
               | You have to assume a direct hit by lightening will fry
               | your hardware, period, full stop - proper grounding and
               | lightning protection however will mean that the hardware
               | does not catch fire.
        
               | Animats wrote:
               | There are lightning protectors that will absorb a direct
               | lightning strike. Most antennas on hilltops and tall
               | buildings have them. They take lightning strikes
               | routinely. Here's some ARRL material on lightning
               | protection.[1]
               | 
               | It's not difficult, but it's not miniature. A classic
               | design was a soup-can sized device with a coax connector
               | on each end and a hulking big ground connection on the
               | can. Inside was a spark gap with dime-sized silver
               | contacts, and a few turns of copper busbar as an inductor
               | to smooth out the spike that got past the spark gap. That
               | goes where the cable enters the building. Similar units
               | today tend to be smaller. There will still be serious
               | metal boxes.[1]
               | 
               | You need a serious ground. As in hulking big copper cable
               | to a long ground rod. Grounding to a pipe is no longer
               | allowed; there might be plastic pipe somewhere in the
               | system, either now or in the future.
               | 
               | The next stage is a "central office protector". This is a
               | gas tube with three terminals - both sides of the line,
               | and ground. So it's an enclosed spark gap in an inert
               | gas. An overvoltage will ionize the gas and short it to
               | ground. Telco central offices have one of those on each
               | line. They're plug-in devices that sometimes have to be
               | replaced.
               | 
               | There's a lot of obviously fake stuff on eBay and Amazon
               | in this area. 2D logos superimposed on curved surfaces,
               | even. There's a standard, UL 497B. If it doesn't have
               | that certification, don't buy.
               | 
               | [1] https://www.polyphaser.com/search?Category=Data+Surge
               | +Protec...
               | 
               | [1] http://www.arrl.org/lightning-protection
        
               | Aloha wrote:
               | Well, Howdy!
               | 
               | I'm a licensed radio amateur since 1996, I've spent about
               | 20 years working in the cellular/telecom/two way radio
               | industry, and I've done Motorola R56 inspections (as well
               | as other proprietary grounding standards).
               | 
               | I respectfully disagree, a direct lightning strike almost
               | certainly will take out gear at a cell site, even when
               | properly grounded. Similarly a direct strike to telco
               | cable will certainly fuse the 16-20ga wire in the cable
               | itself at the first point its near a ground. Carbons,
               | Glass Tubes, and other similar hardware will protect you
               | in the event of a nearby strike (like to a lightning rod
               | on a tower, or building) - but wont save you if the
               | infrastructure is struck itself.
               | 
               | Generally the point of lightning protection systems is to
               | well ground the tower, to draw the lightening away - so
               | the tower and grounding system can protect the equipment
               | - that isn't a direct strike by what I'm saying here - a
               | direct strike would be if it struck the antenna itself.
               | 
               | Thats the perspective I have from cleaning up from
               | strikes at well grounded and protected tower sites.
        
               | Animats wrote:
               | Yes, few antennas really need to remain operational
               | against direct hits. Nor do they usually need to be the
               | highest thing on the tower.
               | 
               | Data cables aren't usually up that high, fortunately.
               | Power cables, though, are. In some areas high tension
               | towers carry a ground wire between the peaks of the
               | towers for lightning protection. It's impressive to see
               | those systems take repeated direct hits without the
               | lights even flickering. I've seen that in Florida.
               | 
               | Worst case is probably is an AM broadcast station where
               | the tower is isolated from the ground at the base. WSM in
               | Nashville TN is like that. They had a pipe ground
               | vaporized and windows blown out in a lightning strike in
               | December 2019. They lost the tower lighting and some
               | transmission components were damaged, but they apparently
               | stayed on the air.
               | 
               | The Empire State Building takes about 25 lightning hits a
               | year. I wonder what their lightning protection looks
               | like.
        
             | upofadown wrote:
             | ... also lightning strikes hitting the ground somewhere in
             | the area. That can induce large voltage differences between
             | the power grounds on the buildings. The voltage difference
             | might be large enough to arc across any isolation provided
             | by the physical network implementation.
        
               | kevin_thibedeau wrote:
               | My neighbor's house was hit by lightning last year and it
               | took out the ethernet ports on two of my devices. Nothing
               | else was affected though. Those devices still work.
               | They're on a PoE switch (though not using PoE) so that
               | may have been part of the cause.
        
           | dekhn wrote:
           | Any long run like this would use optoisolaters.
        
           | aidenn0 wrote:
           | Magnetic coupling removes any issues with potentials, and if
           | it's not AC at the same frequency as what's in the wall, the
           | phase is irrelevant.
        
             | willglynn wrote:
             | I'd like to add a few asterisks:
             | 
             | Magnetic coupling removes issues with potentials _up to the
             | dielectric breakdown voltage_. Ethernet magnetics are
             | considered high potential components, and even the entry
             | level options will isolate at least 1.5kV, but fault events
             | often exceed that figure.
             | 
             | Magnetic coupling removes issues with _common mode_
             | potentials. If the + and - side of a pair are both a
             | thousand volts away from the pair on the secondary side, no
             | problem. If a wire pair suddenly measures a thousand volts
             | across... well, Ethernet transformers are typically wound
             | 1:1.
             | 
             | _Ideal_ magnetic coupling removes issues with potentials.
             | Ideal transformers behave as above, but real transformers
             | have parasitic effects, particularly winding capacitance.
             | Fast transients (including ESD) can and do capacitively
             | couple across the transformer from primary to secondary.
             | 
             | Magnetics are important but do not solve the problem on
             | their own. It is possible to design and manufacture
             | electrically robust copper Ethernet systems - for a given
             | definition of robustness (typically defined as passing some
             | specific EMC test) - but even then real world electrical
             | faults can and do destroy robust Ethernet systems. Fiber
             | has none of these concerns.
        
               | aidenn0 wrote:
               | All very true; good clarifications. In context my point
               | was that it would be totally safe to run a copper
               | Ethernet cable between two houses on separate electrical
               | grids (or even an un-earthed battery powered computer).
        
               | Aloha wrote:
               | Inductive pickup (foreign voltage) from even fairly long
               | runs (20kf +) of well maintained copper is usually much
               | less less than half a volt, measuring either T-R, or
               | T-G/R-G. It's supposed to be floating to ground - nothing
               | on a twisted pair should be ground referenced, if you do
               | have voltage to ground, you have a short.
               | 
               | If it was not floating, you'd get atmospherics, hum, and
               | other issues that you saw in old fashioned ground return
               | systems.
               | 
               | Indeed, measurement of voltage and continuity of T-G and
               | R-G is a standard way to check for faulty cable
        
         | throwaway____10 wrote:
         | What a blast from the past, DSL was an exciting technology.
         | 
         | I did the config and networking of DSLAMs for the first private
         | test installs of Paradyne (Hotwire) DSL hardware in a western
         | state around ~1998-1999, a couple years before DSL really hit
         | the mainstream.
         | 
         | The telecos were slow to move on the technology and didn't do
         | their own centralized rollouts until several years later. We
         | took full advantage of that lead time time to win away a lot of
         | ISDN customers with much lower prices and much faster service.
         | We also saw end of that advantage coming and got out of the
         | business before we had to compete directly with the telecos who
         | could operate at scale and do bundled pricing of the line +
         | service that was harder to compete with. At the time high speed
         | internet over cable was also a while off for the general
         | public.
         | 
         | We also had a tip from a teleco employee that we could use DC
         | Signalling channels / dry copper pairs instead of regular phone
         | circuits (no dial tone, they were meant for alarm service).
         | They cost about 1/2 to 1/3 of the price.
         | 
         | At one point we petitioned to get the local telco to dig up the
         | sidewalk and install several hundred more copper pairs into the
         | building.
         | 
         | It was really interesting to watch the internet access
         | landscape change so quickly.
        
         | netsharc wrote:
         | Al Gore never claimed that, btw, but he did recognize its
         | importance and provided political support, even Vint Cerf said
         | so: https://www.snopes.com/fact-check/internet-of-lies/
        
           | baldfat wrote:
        
           | dekhn wrote:
           | there is an entire multiverse fan fic where Al Gore won the
           | presidential election and we're all living in a post-scarcity
           | society.
        
           | serf wrote:
           | >Al Gore never claimed that, btw,
           | 
           | GORE: "During my service in the United States Congress, I
           | took the initiative in creating the Internet. I took the
           | initiative in moving forward a whole range of initiatives
           | that have proven to be important to our country's economic
           | growth and environmental protection, improvements in our
           | educational system."
           | 
           | There are three ways to read the first sentence, two of which
           | take the presumption that Al Gore invented the internet.
           | 
           | Snopes is so half-wrong that it's getting to be easy to
           | ignore.
           | 
           | In other words , he _did_ say that, he just didn 't mean for
           | people to interpret his ambiguous statement in that fashion.
           | 
           | aside : the word of the day is _initiative_.
        
             | zuminator wrote:
             | Gore absolutely deserves to be dinged for speaking
             | ambiguously in a way that leans towards greatly inflating
             | his contribution to the field.
             | 
             | But at the same time, anyone who's ever read or written a
             | resume will readily recognize "took the initiative in
             | creating" as CV-speak for "I assisted in some capacity,
             | however minor." I expect the actual number of people misled
             | by Gore's self-puffery to have been small to nonexistent.
        
           | Xeoncross wrote:
           | "During my service in the United States Congress, I took the
           | initiative in creating the Internet"
           | 
           | Sounds like we're playing word games at this point.
           | 
           | Imagine that, a politician playing word games.
        
           | baldfat wrote:
           | Why ruin a good meme with FACTS! People
        
             | geozimm wrote:
             | absolutely - a good meme takes on a life of its own...
        
               | geocrasher wrote:
               | Right. Don't want to mess up the AlGoreithms that run the
               | interwebz!
        
         | oasisbob wrote:
         | > While we (PairGain) also made point-to-point private links,
         | it was clear then, and even moreso now that most DSL involves a
         | service provider managing the network - with specialized
         | skills, practices and setup.
         | 
         | Mmm. This brings back memories of running private DSLAMs in a
         | campus environment as a transitional pre-Ethernet stopgap in
         | the early 2000s. 95% of the DSL lines worked great. The
         | remaining 5% were a never-ending nightmare of troubleshooting
         | and sudden breakage.
         | 
         | We didn't want to be DSL experts, we just wanted the hardware
         | to work well-enough for long enough to make it all go away.
        
           | jleahy wrote:
           | I actually ran a private DSLAM to get internet between
           | upstairs and downstairs in my house only a few years ago (not
           | a joke, G.fast).
        
         | kombre wrote:
         | >oh, fiber materials may be sand
         | 
         | what does sand means in this context please ?
        
           | hervature wrote:
           | Fiber optics cables are made of glass whose primary
           | constituent is silicon dioxide and/or quartz which are the
           | primary constituents of sand.
        
             | kombre wrote:
             | oh okay, thx
        
             | NegativeLatency wrote:
             | And therefore should be cheap in a naive estimate
        
               | jaredhallen wrote:
               | To be fair, fiber cable itself is actually pretty cheap
               | in the scheme of things. It's the installation and
               | termination that account for the bulk of the cost
        
         | mbarras_ing wrote:
         | Dr Z! I've recently started at Tunstall Healthcare and you are
         | frequently referenced when refering to SPE. I'm the first
         | person they've had working full time on SPE, so hoping to make
         | some progress :)
        
         | yosheli123 wrote:
         | Awesome to have your input on this. I'd love to talk to you in
         | person to learn more. Reach out at josh@botblox.io
        
         | tomhoward wrote:
         | Cool to see you here on HN. I hadn't heard the name PairGain
         | since I worked for a small corporate ISP in the early 2000s.
         | We'd recommend PairGain modems for clients who needed seriously
         | high-speed links of 2Mbps! This was just before ADSL and SHDSL
         | were rolled out en masse, or at least well before they were
         | reliable enough for corporate use. We had to organise a special
         | installation of a direct copper line from their premises to
         | ours. I guess they just patched them together at the exchange?
         | It was a pretty small catchment area. Fun times!
        
           | EvanAnderson wrote:
           | The tariff in my locality allowed for dry copper pairs to be
           | installed ("burglar alarm circuits") and some of my Customers
           | took advantage of that along w/ PairGain devices to get high
           | speed links between sites serviced out of the same central
           | office.
           | 
           | Relevant article:
           | http://helices.org/commentary/dry_copper_pair.html
        
             | watersb wrote:
             | I can't tell exactly from a quick scan of Cringeley's
             | commentary... but I get the impression that a "dry copper
             | pair" the single-pair POTS equivalent of "dark fiber"...
             | with the critical caveat that a dry copper pair can link
             | two points only if they are serviced by the same central
             | telephone company switch.
        
         | Aloha wrote:
         | I remember seeing your guys HDSL hardware in the field what
         | seems like a million years ago. (for those without a telecom
         | background) It was pretty common as a way to extend T1's
         | without conditioned lines or repeaters then.
         | 
         | Interestingly enough, I'd done direct t-spans's inside of a
         | building over house cable in a situation that was too long (and
         | too poor of cable) to do Ethernet.
        
       | hericium wrote:
       | DSLs were capable of at least 8Mbit/s speeds close to 20 years
       | ago. I worked for a small ISP and where were more than 100 meters
       | (theoretical limit for cat5) between residential buildings, we
       | were setting up 8 modems on a single UTP cable. With home
       | internet speeds back then it wasn't a bottleneck.
        
         | vinay_ys wrote:
         | ADSL2+ can do 22Mbps at 1KM. It can do 10Mbps at 2.8KM. But
         | without mass-manufacturing of the such a switch/access device,
         | it will be expensive.
        
         | hinkley wrote:
         | As long as you weren't stringing those cables off of rooftops.
         | I heard too many stories of lightning strikes burning out a lot
         | of expensive equipment.
        
         | baybal2 wrote:
         | DSL and 10BASE-T1L are not quote the same.
         | 
         | 10BASE-T1L PHY fits on a single chip, without much of analog
         | trickery, and the whole line encoding, signal processing is
         | much simpler.
         | 
         | 10BASE-T1L is what will go into 1 dollar devices, not a $100
         | modem.
        
           | zokier wrote:
           | > 10BASE-T1L is what will go into 1 dollar devices, not a
           | $100 modem.
           | 
           | Which is why this $150 media converter product feels bit
           | baffling tbh.
        
         | RicoElectrico wrote:
         | Wait, can DSL modems talk to each other instead of a DSLAM line
         | card?
        
           | crazyjncsu wrote:
           | Not a traditional dsl modem, but these work well using dsl
           | technology: https://www.amazon.com/Tupavco-Ethernet-Extender-
           | Kit-Repeate...
        
             | iforgotpassword wrote:
             | According to the description this adds at least 660ms of
             | latency, so might be useless for certain applications.
             | Wonder how much the TFA solution adds.
        
             | Dan_Sylveste wrote:
             | I was about to point something like this out.
        
             | xhrpost wrote:
             | That's pretty cool. The specs look like this is both faster
             | and cheaper than the main link of this thread, unless I'm
             | missing something?
        
           | betaby wrote:
           | Most SHDSL and some VDSL can talk each other indeed. Used
           | that capability a lot in 200xs.
        
           | ajb wrote:
           | Its true that the specs are not symmetric in ADSL. The CO
           | (Central Office) end is different from the CPE (Customer
           | Premises Equipment) end, and two CPE devices cannot talk to
           | each other. Among other things, the engineering work had to
           | take into account that at the CO end a bunch of wires would
           | come together and leak RF between each other.
           | 
           | G.SHDSL is more common in a 1:1 configuration (although I
           | think the ends may still be not symmetric) because it was
           | designed as a T1 replacement.
           | 
           | However some devices that could do a single line of CO were
           | made, that can therefore talk to a CPE.
           | 
           | See also https://www.revk.uk/2017/12/its-official-adsl-works-
           | over-wet...
        
           | geocar wrote:
           | Some can at least. I used Netopia SDSL routers without a
           | DSLAM around twenty years ago to serve "high speed internet"
           | in town in the US (Easton Maryland) a few years before they
           | managed to get municipal broadband.
        
           | MrBuddyCasino wrote:
           | It used to be possible many years ago, when I had a DSL modem
           | as PCI card. There was a windows software that would put it
           | in "server mode", and then you could connect another DSL
           | modem to it and "dial in". Not sure if this is possible
           | anymore, but there are Ethernet repeaters that are based on
           | DSL tech which should work in a similar way.
        
           | chmod775 wrote:
           | They may be using the term "modem" loosely here, or rather,
           | more generally than "home modems".
           | 
           | https://en.wikipedia.org/wiki/Modem
        
       | miguel_cordeiro wrote:
       | Love this stuff and was expecting to find more "wild" engineering
       | stories in the comments. Not disappointed!
        
       | yosheli123 wrote:
       | So I built a tiny single pair Ethernet bridge (10BASE-T1L) that
       | can transmit 10mbps over a kilometer on a single pair of twisted
       | copper wires.
       | 
       | Would love to get some feedback for the next iteration
        
         | Aloha wrote:
         | What are the limits on cable characteristics? Capacitance,
         | foreign voltage, etc?
        
         | zakki wrote:
         | Is this full duplex?
        
           | yosheli123 wrote:
           | Yep full duplex
        
         | chriscjcj wrote:
         | Definitely cheaper than StarTech's offering. That's appealing.
         | 
         | https://www.startech.com/en-us/networking-io/110vdslext
         | 
         | However, with StarTech's product, you have a shot at faster
         | speeds if you're going a shorter distance. It can do 75 Mb/s at
         | 300 meters and up to 100 Mb/s at shorter distances.
         | 
         | I would really like to find a similar box that can bond
         | multiple pairs for faster speeds but I haven't found such a
         | device yet.
        
           | tyingq wrote:
           | >Definitely cheaper than StarTech's offering
           | 
           | There are other brands of VDSL extenders. This board seems to
           | be $300 for a pair.
           | 
           | This product, for example, is ~$271 a pair if you buy them at
           | the same time: https://www.netsys-
           | direct.com/products/vdsl2-ethernet-bridge...
           | 
           | And they come with an enclosure and power supply. And a
           | better sort of "step up / step down" bandwidth based on
           | distance...see the chart at the bottom.
        
         | yetihehe wrote:
         | > Any application requiring a simple, low cost, robust
         | connection between physically disparate devices
         | 
         | At $195 it's definitely not low cost.
        
           | [deleted]
        
           | silviot wrote:
           | What's the difference in price between 1km of fiber vs 1km or
           | single pair wire? It might play a role in this solution being
           | cheaper than immediately apparent.
        
             | rkangel wrote:
             | It comes down to whether the cable is there already. If you
             | were laying it, you'd probably go for fibre. But if you've
             | got 1km of some poor quality cable there already, then
             | spending $200 to get usable bandwidth might be a lot
             | cheaper than laying something new.
        
             | DannyBee wrote:
             | The fiber is much cheaper because it's so much more common.
             | 
             | For example: I/O fiber is about 0.10 cents a foot or less
             | for 2 fiber cable. (12 fiber is only 20 cents a foot).
             | 
             | OSP gel-filled direct burial is 0.55 cents a foot or less
             | for 2 fiber cable. (12 fiber is only 65 cents). This is
             | micro-armored OSP cable, resistant to chewing/damage as
             | well.
             | 
             | Basic 18 awg single pair shielded direct burial wire is
             | about 0.80 cents a foot. Can't even find a non-expensive
             | armored version
             | 
             | 10km single fiber transceivers at 10gbps are 40 bucks.
             | 
             | 10km dual fiber transceivers at 10gbps at 29 bucks.
             | 
             | It would be much cheaper, more effective, and a better
             | result to just use fiber for 1km here.
             | 
             | You could easily bury 12 fiber cable and use it for the
             | price you will pay to use single-twisted-pair.
        
               | Aloha wrote:
               | When everyone prices fiber, they fail to include the
               | termination costs.
               | 
               | How much are the termination costs on that fiber, per
               | run?
               | 
               | Also, you'd never install single pair direct burial, and
               | almost never shielded (unless its audio and not phone
               | type) - it'd be 4/6/12 pair direct bury gel-filled cable.
        
               | xenadu02 wrote:
               | Besides what DannyBee says about termination being a lot
               | cheaper and easier when you can tolerate small losses
               | (which is most people):
               | 
               | Big infrastructure often orders the cables pre-
               | terminated, eg an ISP will order their arial cable with
               | built-in termination at certain intervals. No muss, no
               | fuss.
               | 
               | You're right about single pair though. If you're putting
               | in two strands might as well do 6. If you need 6 might as
               | well do 24. Never hurts to have spares and extra
               | capacity. Especially if it involves stringing poles or
               | digging holes.
        
               | DannyBee wrote:
               | Termination is basically a non-cost anymore. The price a
               | pack of 10 sc/apc field terminations (IE that a random
               | DIY'ers could do) is <20 bucks, and to your question, the
               | same as a price of a pack of 10 ez-r45 connectors.
               | 
               | The loss and ease of mechanical connectors has gotten
               | good enough (0.15 db or better) that most of the folks i
               | know will only fusion splice when they really have to.
               | 
               | I agree it wouldn't make sense to do single pair or
               | single fiber, but that's the actually the comparison at
               | which 10baset-1l is _at all_ competitive.
               | 
               | I have buried a _lot_ of fiber, and a _lot_ of network
               | cable over the years :)
               | 
               | I was just trying to be fair and present the best case
               | for 10baseT1L
               | 
               | In practice you can do 12/24 strand fiber (or 6 strand
               | fiber + power + whatever) for less than the price of
               | whatever particular set of 18 awg twisted pair (which is
               | what the spec requires at 1km) + other things you wanted.
               | The cable would be smaller, and if you use A3 or B3
               | fiber, it would be more flexible/support a lower bend
               | radius than the 18 awg twisted pair. By far. IT's not
               | even close.
        
               | jandrese wrote:
               | This product makes sense if you are reusing existing
               | copper lines.
        
               | DannyBee wrote:
               | in which case unless you have 18awg copper lines around,
               | you can't do 1km :)
               | 
               | I would be shocked if anyone has those. Maybe alarm wire
               | I guess?
        
               | p1mrx wrote:
               | > 0.80 cents a foot
               | 
               | Isn't that 80 cents/foot, or 0.80 dollars/foot?
        
               | bufferoverflow wrote:
               | Aren't you off by a factor of 100? Maybe dollars per
               | foot, not cents per foot?
        
               | icedchai wrote:
               | If you're in the position to bury new fiber cable, why
               | would you use this product?
        
               | DannyBee wrote:
               | To get to 1km, the spec requires 18awg cable, which
               | nobody has around either ;)
        
             | withinboredom wrote:
             | A copper wire can be bent in just about every which way
             | (such as tangled when being tethered to an underwater
             | drone), while fiber cannot.
        
             | eru wrote:
             | I don't think the wire itself would be the expense, but the
             | laying of it?
        
               | voakbasda wrote:
               | The cost of laying wire is virtually the same as laying
               | fiber, so the difference really comes down to the
               | material costs. The only good reason to use wire would be
               | existing installations, as you sidestep that cost
               | entirely.
        
               | EUROCARE wrote:
               | But perhaps the wire is already there. I don't think
               | anybody advocates for building entirely new datalinks
               | using this. Laying another 1km of cable is much more
               | expensive than 2x200 USD to reuse existing cable.
        
           | kube-system wrote:
           | "Low cost" is relative. For parts in the industrial/robotics
           | space, $195 is not expensive.
           | 
           | You can certainly spend more on other options:
           | https://westwardsales.com/patton-cl2300e-ethernet-extender
        
             | jeroenhd wrote:
             | You can get full products that do higher speeds over longer
             | distances at lower cost, search term "vdsl repeater".
             | 
             | It's possible that this product handles bad wiring better
             | as it's ethernet rather than VDSL2, but I think those
             | devices are a much better fit.
             | 
             | One thing that might be better with an ethernet based
             | standard is the ability to add multiple stations to the
             | same link, relying on ethernet's error correction.
        
       | ComputerGuru wrote:
       | The schematic/drawing says 2000 meter range, the title and
       | description say 1km. Not sure which to believe!
        
       | tiffanyh wrote:
       | Most don't realize, you can run 400mbps of data over your old in-
       | home electrical wiring.
       | 
       | https://www.digitaltrends.com/computing/everything-you-need-...
        
         | RedShift1 wrote:
         | My experience with powerline adapters is that they all fail
         | sooner or later... I think 230 V is just too much to handle in
         | a small package combined with sensitive low voltage
         | communication chips.
        
         | icedchai wrote:
         | I experimented with powerline network adapters for a while. You
         | might see 400 megabits on the same circuit. Between floors in
         | your house on different circuits? Very unlikely. The latency
         | was also pretty bad compared to wifi.
        
           | tumetab1 wrote:
           | My experience is also that between floors (circuits) you
           | loose bandwidth. With latency I see no issue and I find that
           | weird.
           | 
           | Latency, with Wi-Fi or not, it's probably correlated with
           | transmission failures so there probably some bad circuitry or
           | devices than create noise (like electrical motors).
        
         | worldofmatthew wrote:
         | Depending on the country, you can be made responsible for radio
         | interference.
        
       | worldofmatthew wrote:
       | Some questions:
       | 
       | 1. Would you need two of them at a $430 cost for this?
       | 
       | 2. If so would the person be much better with alternative
       | solutions like fixed wireless or Ethernet-VDSL2 conversion that
       | would deliver much better performance at this price point?
        
         | mrjin wrote:
         | Further more, why would someone choose this over $59.69 a pair
         | fiber ether net media converter, up to 20KM, 1000Mbps from TP-
         | LINK? There are most likely cheaper options from other vendors.
         | 
         | https://www.aliexpress.com/item/1005001435649462.html
        
         | numpad0 wrote:
         | These emerging Ethernet standards are cost effective upgrades
         | for large industrial objects like warehouses and monstrous
         | vehicles.
         | 
         | You may have an unused phone line or just some reserved pins in
         | a connector, and the cable runs a quarter mile to the other end
         | of "this". The existing solution is working, albeit
         | inconvenient, and it will be _nice_ to be able to just add
         | Ethernet telemetry or control to it. That's where these shine.
        
         | xattt wrote:
         | The economics in buying this is whether re-running the 1-km of
         | copper with whatever media you want will cost $430 or less.
         | 
         | I think just rolling a telecom truck will cost you this.
        
           | yosheli123 wrote:
           | Yeah fair. I'm aiming at new space constrained applications
           | with this.
        
         | yosheli123 wrote:
         | Yeah approx $400 for a pair. Mainly chip shortage messiness, I
         | think I can get the cost down to less than $200 a pair in April
         | 2023.
         | 
         | Regarding VSDL, never used it myself; I guess it would come
         | down to space/power considerations. I haven't seen VDSL used
         | much in the industrial automation, single pair ethernet seems
         | to be the preferred choice.
        
           | worldofmatthew wrote:
           | Long range networking is a very overcrowded market. You need
           | something that is either really good or really cheap.
        
       | jmpman wrote:
       | What's the best way to do this underwater? I need to go across a
       | lake about 1km.
        
         | dhon_ wrote:
         | You might be better off with directional wifi antennas if
         | appropriate for your application.
        
           | [deleted]
        
         | mrjin wrote:
         | Fiber I recon.
        
         | yosheli123 wrote:
         | You'd use some standard tether cable, Blue Robotics sell good
         | stuff for that.
         | 
         | https://bluerobotics.com/store/cables-connectors/cables/fath...
         | 
         | Then just straight onto the screw terminals.
        
       | transistor-man wrote:
       | Awesome project!
       | 
       | This would be fairly great fit for underwater UAV's, or like
       | security camera way out on the edge of property. May be a good
       | idea to post on ardu-sub related discussion forums. I'm not aware
       | of an off the shelf module that's point to point ADSL, almost
       | every modem is intended to yell at a ADSL / ADSL2+ host.
       | 
       | Did you run into any issues with consumer-grade gigabit switches
       | negotiating 10Mbit?
        
         | 0xfaded wrote:
         | Blue Robotics sells the fathomX exactly for this purpose. I
         | wouldn't be surprised if it uses the same chip set.
         | 
         | https://bluerobotics.com/store/comm-control-power/tether-int...
        
           | yosheli123 wrote:
           | That tops out at around 300meters. Ours goes beyond 1km.
           | Still there's is awesome for camera feeds; I love the Blue
           | Robotics hardware, SPEBlox Long is just a different
           | application (more industrial automation focussed)
        
         | transistor-man wrote:
         | Any chance you're going to release schematics / open source the
         | design?
        
       | hotpotamus wrote:
       | It seems that single mode fiber is king for long distance cable
       | runs now, nevermind that it can push gigabits. What kind of cable
       | would this be and is it actually much cheaper? My impression is
       | that most cost of cabling now is the labor to run it as opposed
       | to the medium, but I'm a neophyte for sure.
        
         | time0ut wrote:
         | A common use case for this is to use existing infrastructure
         | like in an industrial setting. You can also provide power over
         | a cable like this.
        
         | mschuster91 wrote:
         | Fiber has the downside of being extremely vulnerable to
         | mechanical damage or dirt and expensive on long runs. This here
         | runs on virtually anything that's twisted-pair wire.
        
         | throw0101a wrote:
         | > _It seems that single mode fiber is king for long distance
         | cable runs now, nevermind that it can push gigabits._
         | 
         | Bandwidth isn't the only consideration: you can deliver power
         | over copper:
         | 
         | * https://en.wikipedia.org/wiki/Power_over_Ethernet#PoDL
         | 
         | * https://www.ti.com.cn/cn/lit/an/snvaa25/snvaa25.pdf
        
           | DannyBee wrote:
           | Main reason POE is useful is that it lets you deliver power
           | over existing wires. If you are running new wires, you can
           | already do what you want.
           | 
           | They make plenty of fiber+power in single cable, because the
           | fiber is unaffected by the power.
           | 
           | Running 1km of slow, expensive, single-pair cable to run low-
           | data rate + power, vs fiber+power cable saves you essentially
           | one connector. For very high cost - in money and loss of
           | bandwidth.
           | 
           | Plus 10base-t1l is not common, so the price of equipment is
           | high as well.
        
         | yosheli123 wrote:
         | Basically just any CAT5e like twisted pair has worked for me up
         | to 1km. 26AWG unshielded twisted pair basically, 100Ohm diff
         | impedance. Cost of cabling is pennies IMO. Labor cost, who
         | knows.
         | 
         | Optical can be quite expensive though these boards aren't
         | exactly cheap (yet).
        
           | hotpotamus wrote:
           | I've actually had to deal with fiber for the first time in my
           | career recently and it was actually easier and cheaper than I
           | imagined. I think my take on costs was about a decade out of
           | date and things have gotten pretty affordable these days (for
           | 1Gbps at long range at least). Probably all the fiber to the
           | home providers have pushed the economies of scale on these
           | things.
           | 
           | But here's sort of an example of what I'm talking about.
           | 
           | https://www.amazon.com/Gigabit-Ethernet-
           | Converter-1000Base-L...
           | 
           | So the cost is pretty low if you wanted to terminate with
           | these (these things aren't too loved in networking circles,
           | but I can vouch that they do work), then the biggest
           | difference is the cost of bulk cable - fiber vs copper. I
           | assume the cost of labor to run it is essentially the same.
           | 
           | The main tradeoffs I see are that you can run power over catX
           | cable (though probably not 1km?) but single mode fiber seems
           | to be indefinitely able to upgrade bandwidth; I'm told that
           | old installations from the 90's are still used and are
           | pushing 100's of gigabits with newer optics attached to them.
           | 
           | Like I said, I'm fairly new to this having started a job
           | where I have to talk to datacenter people about this sort of
           | thing, so I'm learning a bit as I go.
        
           | DannyBee wrote:
           | Optical is not expensive anymore. It's 20 bucks for 10gbps
           | transceivers. The cable is much cheaper than twisted pair.
           | termination will take you no longer than a network cable.
           | 
           | The world is not the same as it was 15 years ago :)
        
         | madengr wrote:
         | I wired my house with 62/125 fiber 22 years ago as a 1 km spool
         | was only $250. I'm too lazy to look it up, but I suspect
         | multimode fiber is cheaper than copper, and termination kits
         | are cheap now.
         | 
         | I'm running 10G on single mode 100 ft jumpers to a few
         | computers in the house and that's cheap too. SFP are $35 but
         | the NIC are more.
        
           | hotpotamus wrote:
           | Yeah, multimode fiber seems to be the red headed step child
           | of the networking world these days, but that's a good
           | question about the cost of it vs copper. It's just plastic,
           | right? It seems like a good option for high speed SOHO or
           | perhaps within rack networking. But if I was running cable in
           | my house today, I think I'd still go copper for PoE
           | capability.
        
             | madengr wrote:
        
       | trollied wrote:
       | A few years ago, revk (owner of an ISP in the UK) did ADSL over
       | wet string: https://www.revk.uk/2017/12/its-official-adsl-works-
       | over-wet...
        
         | yosheli123 wrote:
         | That's brilliant!
        
         | xhrpost wrote:
         | There's also Ethernet over barbed wire:
         | http://www.sigcon.com/Pubs/edn/SoGoodBarbedWire.htm
        
           | gorkish wrote:
           | Back in the day I ran X.25 over an actual barbed wire fence
           | for a customer. It connected a serial terminal in a field
           | house at a local feedyard back to their SCO box in the main
           | office. Probably about 1500 feet. It was reliable!
        
           | rlonstein wrote:
           | Paraphrasing the old joke about getting a dry pair, must be
           | an SBC customer.
        
           | justcodin wrote:
           | wow
        
         | aidos wrote:
         | The HN post at the time:
         | https://news.ycombinator.com/item?id=29440681
         | 
         | RevK is the owner of AAISP (an xkcd/806 compliant
         | organisation).
        
           | ComputerGuru wrote:
           | https://xkcd.com/806/
           | 
           | https://www.revk.uk/2010/10/xkcd806-compliance.html?m=1
        
       | jokoon wrote:
       | I guess it's also a latency tradeoff?
        
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