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.
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.
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!
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.
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.
A leased loop is any arrangement where a customer pays the telco for a dedicated loop for continuous use. A dry loop is a type of leased loop that isn't connected to any telco equipment, just spliced together to create a continuous circuit (a typical or 'wet' leased loop has at least battery and sometimes dial tone from the telephone switch). It's perfectly possible to get a leased line that spans telco offices, in which case your loop has to be spliced to an interoffice or toll lead (long distance line). In the days before heavy use of multiplexing, toll leads were scarce and so interoffice leased lines were extremely expensive.
Dry loops were often sold as burglar alarm circuits because one of the most common uses was for burglar alarm communicators that often operated on polarity reversal - meaning that they applied a potential to the pair and just swapped its polarity when an alarm condition occurred. Of course there were more sophisticated burglar alarm communicators at the time that used telegraphy techniques, but these usually ran on private networks since they could share a bus in a way that was not typical of telco infrastructure (most of these were basically Gamewell systems even if not made by Gamewell proper). In the early days of burglar alarm monitoring, if the monitoring service didn't have a private network (typical in urban areas) they usually installed their monitoring equipment or a multiplexing system at each telephone exchange in the covered area, allowing for more economical dry loops within a single office. Actually this pattern continued well into the '90s with some burglar alarm services using DSL-like high-frequency digital communicators that interacted with a monitoring system that had to be connected to the line card at the telephone exchange.
1990s AppleTalk networks could work over a single pair. I ran a network with hundreds of Macs for a tech company. Ten buildings in a small campus.
Still remember the day the fire-alarm techs punched down over one of the Macs in the executive office. Not much of a network signal when there's 24 Volts on the same line.
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.
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)
Lots of comments about lightning, but I believe you are referring to a "ground loop" where the ground/neutral at one site is offset from that of a different site tens or hundreds of meters away. This is why all commonly used RJ-45 Ethernet connections use differential signalling and have the tx/rx pairs isolated by transformers. (Note that PoE Ethernet can still create similar problems if one is not careful.)
Here's a relevant news article about a lawsuit related to this phenomenon:
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.
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.
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.
I was initially a skeptic of the cost of Fibre-To-The-Premises, but in hindsight for New Zealand (≈Oregon) I think a national rollout of fibre was very effective[3][4].
AFAIK fibre is more resilient to catastrophes (like earthquakes[1][2] in Christchurch or California), and having a high speed residential fibre network definitely helped during Covid.
I am uncertain what you mean by “efficient”. Perhaps link to something that backs up your opinion?
Australia and New Zealand have helpfully agreed to provide a case study in which works best. Mixed fibre and copper in Australia is slower and ended up costing dramatically more than it was supposed to.
I think it's just inertia. At higher speeds you have to do so much signal processing going over copper, that it iss costing more and more energy compared to optical. Which is limited to 2.5 Watts per port and end of the fiber, at least in common prosumer facing gear. While you can push up to 80KM(or meanwhile even more!) in one run with such stuff, depending on the used fibre and wavelength.
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"...
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.
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.
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).
I'm using a 1gbps symmetric connection at the office, for the last decade or so. The network speed is limited by my NIC and the cabling to the switch. The network at the office has more bandwidth (we're the network backbone).
We have fiber ran into our apartment buildings. My apartment's termination box is at the wall across my flat door. On the other hand, the speed I can get from that fiber is not higher than the current VDSL offerings, and they both cap at 100mbps downstream (upstream is probably limited at the same speeds with VDSL). Since the FTTN box is also outside, the speeds and stability from that VDSL connection is rock solid.
For no apparent speed advantage, I need to terminate a thick fiber, and need to run it in the open across the house, drilling walls in the process, or move my house's whole internet infrastructure near it. Both are illogical given the floor plan of my house.
Then comes the equipment part. Again, I'll need to change my core router at home and change everything (I have a mesh network at home), or cascade it to ISPs fiber router, which is another box, more cables, and more management. If the ISP allows me to use my own router, I'd need a media converter from fiber to copper. Which's again more cables, more boxes, more management.
As a result, I'd rather use my house's in-wall cabling to get the speeds I'm happy with instead of getting a shiny (pun intended) technology with no speed advantage.
If the speeds offered here changes over time, I can re-evaluate my choices, but as the xDSL technology gets better, I'm guessing that it'll keep the same speeds with fiber offerings, at least for residential stuff in my area. So, I project that I can upgrade my network speeds at least for a decade without changing my network equipment or cabling.
Sorry I should have been clearer: I am referring to "Sonic Fiber" which is their own infrastructure, not any kind of resold service which they do offer in areas where they have not deployed their own fiber infrastructure.
In the Bay Area they have fiber in SF, South SF, Daly City, Redwood City, Berkley, Oakland, San Carlos, Burlingame, Albany, Brentwood, and probably more. They are rolling it out mostly in areas with poles at the moment because the cost of burying is quite high.
They've proposed "microtrenching" in SF to reach areas with all underground utilities but so far the city hasn't been very interested and it isn't cost-effective for them to dig up the sidewalks to install conduit. I hope that will change at some point.
When AT&T did a fiber overlay in San Jose (GPON), they had neighborhood cables that were factory terminated to go from wherever to each pole. The linemen had to setup the pulleys? and pull the cable through, and attach them, but they didn't have to terminate them. When they ran a line to my house, they did do a field termination, but it seemed like they had a tool and it went quickly (mine was the tech's first time, or at least pretty early, but it only took a minute or so).
Of course, for repair work, if a tree or something breaks a multi fiber bundle, splicing is going to be a lot harder than coax. Probably harder than traditional phone lines, but I think PON is setup so that you don't need to care which wire connects to which other wire, and if you do that for end-user traditional phone lines, you'll have a big mess, so you'd really want to match the wires up before you junction them. Coax is just one big wire, so way simpler.
DOCSIS is capable of 3gbps over coaxial cable and there is more room to improve, so fiber doesn't have a significant advantage in terms of possible bandwidth. Because DOCSIS was designed to operate on the cable network, which was designed to reach a very large number of homes, the architecture of the system tends to be more cost-effective than fiber. The fiber equivalent of a cable-like topology, and what is used by fiber ISPs, is PON, but PON is actually relatively limited in terms of both range and number of service points compared to DOCSIS on cable. A typical PON installation requires more field equipment to serve the same customers at the same rate compared to DOCSIS.
This is made worse by the issue of power distribution: the field equipment for DOCSIS consists of distribution amplifiers which are powered over the coaxial cable itself, allowing the battery-backed power supplies to be placed at convenient locations. There's not really any equivalent of this for PON, so extending PON networks beyond a single loop (depends a lot but typically a few KM and <100 customers) requires an OLT which is relatively large and needs separate power provisioned. You can put OLTs in serving area cabinets but this is costlier compared to cable equipment.
Another major factor is the customer premises: most homes already have coaxial cable distribution installed that is either compatible with DOCSIS 3 or can be made compatible with DOCSIS 3 by replacing the distribution amplifier or passive tap, which is a fairly cheap and fast operation. Installing PON to customers requires getting fiber to their house, and then either an outdoor ONT (troublesome from a maintenance perspective) and ethernet into the building or fiber into the building. The equipment here doesn't necessarily cost much but the labor of running new lines into customer homes is substantial and makes signing up new customers much higher-friction.
Most of the time when a cable provider upgrades to introduce DOCSIS 3 for digital voice and internet they aren't really replacing any cable anyway, just distribution amplifiers and nodes. The cost of this work is significantly lower than running new cable and it doesn't require new pole attachment agreements etc.
In general, in urban environments with existing cable TV plant there are few upsides to fiber. Urban fiber in existing areas is usually only cost effective when it's a new ISP competing with the cable company.
Finally, most DOCSIS networks are in a process of transitioning from CMTS (cable modem termination system, the upstream end) in the cable headend to a compact serving area CMTS at each amplifier point. This is called "Node+0" architecture, meaning there is a fiber node and then zero distribution amplifiers before the customer. One of the nice things about the cable "HFC" or hybrid fiber/coaxial network is that it is relatively easy to make this transition progressively as you sign up additional customers, since CMTS nodes have been made very small. PON is less forgiving this way and requires more up-front capacity planning, especially since network expansion means the permitting process on relatively large curb cabinets or enclosures.
... 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.
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.
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.
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.
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.
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.
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.
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.
Clearly you have never seen a phone line fried by a direct lightning strike before: the cable vaporizes and blows up the ground over top of it. Direct strikes are rare enough that most people will never see them. On overhead lines the neutral and communications strand are grounded and will take most of the strike over the twisted pair communications cable. Underground cables have some benefits by being in non-conductive conduit, but none of that matters if it's a direct strike. All insulators will break down in a strong enough electric field.
There's also the issue of ground bounce. A lightning strike near a house will feed back into the telecommunications and power equipment via the ground rod/plate. I've had experience with plenty of modems getting fried over the years. Some places are just lightning magnets.
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.
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).
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
Unless the telco cut the outer shielding on the twisted pair cables everywhere a terminal was installed. That was one of the remediations the incumbent had to undertake here when they started deploying 50Mbps VDSL2 FTTN service. Oops.
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.
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 résumé 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.
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 :)
> 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.
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.
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
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!
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.
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.
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.
I've got a 3 pair run[1] to my gate with a keypad gate controller. Two pair are used for voice communications, and one pair is idle. The gate controller has 10 base T ethernet (for management), but you need two pair, and it's maybe a touch outside the distance spec for 10baseT. I'm not quite ready to spend $350 to get it on ethernet though.
[1] Actually, it's 4 pair to an in-ground junction box, where it splices to 3 pair to the gate controller. For $350, I have maybe some other other options around the junction box (I've already got some passive 10baseT <-> single pair devices, but they don't work at the full distance. Probably would work at the junction box, if I had a powered ethernet switch there, but I need weatherproofing.
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.
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.
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.
Yeah, from a cost/redundancy/etc perspective it rarely would make sense to run 1.
I will get pre-terminated for MTP runs, but not for anything else. Fusion splicing connectors just isn't slow (and if i need to go quick, i'll just splice a pigtail onto it until it fails)
I agree for redundancy, etc, better to just add more until loss-of-ROI occurs, but will say doing something for extra capacity for home users/even business users feels like massive overkill these days.
Even 2km 100G duplex transceivers for SMF are <$200 a piece now.
Cost is dropping crazily fast.
(bidi simplex ones now also exist on fs.com as of a month or two ago, but are still way too expensive)
It's dollars per foot, yes.
Honestly though, since they are all in the same relative scale, and the point is what was cheaper and by what percent, this feels like pedantry.
Put another way - outside of being technically correct, why does it matter to the point at hand?
I pay about $350 per kilometer for 24 count flat all dielectric G.657A1 fibre with 2 x 2.0mm fibreglass strength members. Add about $100 for shipping from overseas.
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.
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.
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.
Whatever EUROCARE said about existing installations applies.
Though what I had in mind was that when I was handling optical fibre as a layman (we have fibre to the living room here in Singapore), that fibre is a lot more delicate, so would require a bit more care to handle than copper. But I guess that's probably not a major cost factor, if eg you have to dig a trench for your cable.
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.
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.
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
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.
In the context of the current thread, I'd say that's fair. If you're talking urban infrastructure, my understanding is that things are good until the existing (fairly large) conduits fill up, and then everything stops until someone digs up the street for blocks and blocks.
Do you happen to know, for these long conduits is it typical to do a solid run or to put access panels at regular intervals? If you're running a new cable are you actually trying to run a 1km snake through a pipe, a 100m snake 10 times, 50m x20, or something in between?.
I've never seen anyone run a 1km cable, but I've seen buildings be rewired with tens of kilometers of new cables a couple times.
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?
Blowing the fibre or cable with compressed air through the empty 'speed pipes'.
As in one end of the fibre is connected to some sort of plug, while the rest is on a spool, the plug is then inserted into a narrow pipe, and pushed through it by pressure.
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.
There aren't that many types of fiber optic cable, the actual cable diameter is extremely small (single mode might have 9µm 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.
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.
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.
I think this is more a usecase for places where you already have a copper cable available (eg. telephone cable between buildings). If you have to dig and pull a new cable, doing fiber is the only logical choice now, but the price for all that is way way above $120.
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.
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.
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.
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.
It's a low volume product. If there were a 100k produced the cost would be substantially lower. Not that many people need 1.6km 10Mbps connections, and many of those that do need a 1.6km connection will want more than 10Mbps.
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.
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.
One catch is that ISPs rolling out VDSL, such as CenturyLink, are often using pair bonding. So despite a typical performance limit of 40/10, CL offers 80/20 in VDSL markets by taking advantage of the fact that homes are typically wired for two lines.
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?
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.
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.
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.
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?
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.
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.
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.
There are actually different models have laser trans-receivers built in with same or might even cheaper price. So unless there are very special requirements, I don't really see a reason to go for those.
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?
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)
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.
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).
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.
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.
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 :)
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.
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.
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.
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.
Yeah, POE is great. I have a 48 port Ubiquiti switch with POE AP and cameras. I ran duplex fiber and 2 pair of shielded CAT 5 to each room. For the downstairs rooms, those are through short runs of conduit to the basement, so I can poke whatever else through there, like the single mode jumpers. I should have run conduit upstairs, but I do have a 4" PVC running from basement to attic, so I could run single mode upstairs, but would require drilling and fishing.
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).
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.
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.
Single pair communications are invaluable in industrial applications - almost all of our scenarios involve the restriction of not being able to run new cable. The costs involved in running new cables can be eye watering to say the least. If you're on a greenfield project, then there are surely better solutions since you have the luxury of designing the cable runs.
VDSL has been king in the areas I work in for quite a few years now and has been very reliable. We are experimenting with SPE and it's looking positive with the biggest benefit being cost. SPE for us is a significant cost down that will allow us to design it into more products where VDSL blew the BOM budget. We'll still use VDSL when we need higher bandwidth but only have that single copper pair.
SPE fills a gap where you need a decent amount of bandwidth at a reasonable distance for a low price. For us it complements modbus, standard ethernet, vdsl etc.
SPE is also very new with the chipsets really only starting to become available in the last 12 months or so. Chip shortages aren't helping but expect to start seeing these solutions pop up all over the place.
SPE looks really interesting for CAN/RS485 replacement.
I just noticed Analog devices also has chips finally available even at resellers: ADIN1100 for pure phy like the TI part in this but more interesting once are ADIN1110 (spi bus to MAC+PHY so any mcu with spi bus can communicate with ethernet) and especially ADIN2111 which is 2xSPE PHY + MAC + spi bus so with single chip you can make daisy-chain devices talking at 10base-t1l and the ADIN2111 has simplified rx/tx interface so with small transformer nice galvanically seperated link can be made.
Until now I have used isolated CAN transceivers for links between devices that need ~100m distance as quite many MCU have built-in CAN peripherals but ethernet MAC is usually restricted to the bigger series. The spi bus on the ADIN (and probably later some other chips similar to the ENCJ from microchip) opens this up to smaller lower end devices.
I am really excited for the coming years as I have been waiting for these 10base-T1L devices to be available for roughly two years and the chip shortage in general has not made things easier.
Considering MoCA ethernet to coax will do >1Gbps over 1km distances for the same price, I'm failing to see the use case unless you absolutely have to reuse an existing wire pair. Ultra lower power applications maybe?
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 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.
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
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.
Not sure how I'd feel about have 1km ethernet links without monitoring-- in particular, being able to catch pre-fail stats getting worse when it's wet out and being able to TDR the interface remotely so when it fails I've got some idea if it was cut near one end or the other before I go out to fix it.
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.
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).
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.
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?
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.
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.