> how does [100BASE-TX] save power vs [1000BASE-T] running at low throughput?
100BASE-TX uses just two pairs (lanes), one for sending and one for receiving. 1000BASE-T uses all four pairs, for both sending and receiving. Therefore, a 100BASE-TX interface that's only receiving needs to power up one pair. A 1000BASE-T interface needs to power all four pairs all the time.
I recall reading about some extensions that allow switching off some of the pairs some of the time ("Green Ethernet"), but I think that they require support on both sides of the link, and I'm not sure if they are widely deployed.
My only annoyance with "Green Ethernet" things is that often they seem to work poorly.
The dedicated machine I still keep around for Windows things has two onboard 2.5GbE ports. It will apparently sometimes, even with all power saving features turned off, randomly negotiate down to 100 mbit if I leave the machine alone for a bit, and then stay at that speed forever unless I manually reset the link after wondering why transferring large amounts of data is bottlenecking severely.
100 mode saved me once when I really really really needed to have a connection in that moment, but the ethernet cable glued to the wall that I was using had only three out of eight wires even functioning.
According to the technician I spoke with, he could only detect three on their end.
The cable was chewed through by cats, so perhaps it was three just in that moment.
Is that really true? If so, is there a saner way to handle this than upgrade all the things to 10GBE? Like a POE ethernet condom that interfaces with both network and devices at native max speeds without the core network having to degrade?
Isn’t that only relevant for network topologies that rely heavily on broadcasting to multiple nodes. Eg token ring, WiFi and powerline adapters?
For regular Ethernet, the switch will have a table of which IPs are on which NIC and thus can dynamically send packets at the right transmission protocols supported by those NICs without degrading the service of other NICs.
I’ve seen some vlans hit 1mbit BUM filters, I think we had about 800 users on that one. To saturate a 10m link would require a help of a lot of broadcast traffic.
100m is fine. 10m is fine but I can’t think of anything that negotiates 10m other than maybe WOL (I don’t use it enough to be sure from memory).
If I didn ahve something esoteric it would be on a specialised vlan anyway.
I also appreciate the 10/100 support. I recently needed it for some old voip equipment, and it was shockingly difficult to find an SFP+ module that worked in my 10G switch and supported 100mbps.
I'm guessing different mainboards could offer better USB port support for Gen 2 2x2, but right now the Ryzen AI 13" chips at least top out at USB4 / 3.2 Gen 2x1
I bought this one when upgrading my desktop, it indeed delivers what it promises. 14.5GB/s on my tiny random desktop, it's impressive. Everything feels so instantaneous, my Linux desktop finally feels like a Mac :)
That's certainly impossible as even USB4 is only 40Gb/s~5GB/s, and of that you could only expect to get 32Gb/s~4GB/s. Or realistically even less due to overhead.
It is probably the speed of it being read into RAM.
Try entering sync right after copying to see how long it really takes
What you're seeing are the speeds of various multi-tier caches (RAM, intermediate SLC etc.) It cannot write to its main flash memory that fast. While it to the user looks like they just wrote 10 GiB in a single second, the SSD is internally still busy for another 10 seconds persisting that data. The actual real write speed of top-shelf consumer grade SSDs these days is somewhere in the vicinity of 1.5 GiB/s. Most models top out at half of that or less.
I have one of these, though I'm using with a USB 3.x port as that's what my desktop has. For me it's working fine, and for others with actual USB 4 ports it seems to be working properly for them.
I am definitely not the person to shed any light on what is going on, but you've added to my feeling that these adapters are all incomprehensible, so I'll try and do the same for you.
I have a USB C ethernet adapter (a Belkin USB-C to Ethernet + Charge Adapter which I recommend if you need it). I ran out of USB C ports one day, and plugged it through a USB C to USB A adapter instead. I must have done an fast.com speed-test to make sure it wasn't going to slow things down drastically, and found that the latency was lower! Not a huge amount, and I think the max speed was quicker without the adapter. But still, lower latency through a $1.50 Essager USB C to USB A adapter, bought from Shein or Shopee or somewhere silly!
I tried tons of times, back and forward, with the adapter a few times, then without the adapter a few times. Even on multiple laptops. As much as I don't want to, I keep seeing lower latency through this cheap adapter.
Next step, I'll try USB C to USB A, then back through a USB A to USB C adapter. Who knows how fast my internet could be!
My laptop refuses to charge for 45W chargers as well, but I can almost understand it.
When plugged into 100W chargers while powered on, it takes ten minutes to gain a single percentage point. Idle in power save may let me charge the thing in a few hours. If I start playing video, the battery slowly drains.
If your laptop is part space heater, like most laptops with Nvidia GPUs in them seem to be, using a low power adapter like that is pretty useless.
Also, 100W chargers are what, 25 euros these days? An OEM charger costs about 120 so the USB-C plan still works out.
Other manufacturers do similar things. Apple accepts lower wattage chargers (because that's what they sell themselves) but they ignore two power negotiation standards and only supports the very latest, which isn't in many affordable chargers, limiting the fast charge capacity for third parties.
Which laptop is that? My Razer with 5070 will take 45W chargers just fine, so do the ThinkPads, my work 16" MacBook and previous Asus Zephyrus with 4070.
I was on a trip a few years ago and had only brought my “compact” 45w usb-c charger since the brick that came with my work ThinkPad (one of the high end 16” screen models, maybe p16?) was enormous. When I plugged it in Windows complained that the charger was insufficient to charge the laptop. I think it at least kept it from draining the battery though. I had to run to Walmart and get a 65w charger which did the job fine.
The idea is that you can use chargers that you have lying around. In an emergency I charged my MacBook Pro with an old 5 or 10W adapter overnight while shut down. I don’t see the reason for flat out refusing a charge. Especially when turned off.
I gotta say, I love my macbooks. Every Apple laptop I've owned that has USB-C ports will happily charge itself from a 5V/1.5A wall charger (albeit extremely slowly).
That hasn’t been my experience. I once tried to charge an M3 MBP via a lower powered wall plug. It was left off over night and the following morning the battery was still at 1%.
This was a decent USB plug from Anker. I regularly use it to charge things like iPhones and tablets. I knew it wouldn’t supply enough power to run the MBP but thought it should trickle charge the device over night. But it didn’t.
I can’t recall which cable I used though. The cable might have been garbage but I’m pretty sure I threw out all the older USB cables so they wouldn’t get mixed with more modern supporting cables.
My work has a little power strip with a usb-c and usb-a jack on it at every desk. I can charge my phone and iPad just fine with a USB-C cable into the USB-C port, but when I plugged my MacBook Air into it, it says “not charging.” Going into the system information tool I can see it’s only running at 10W. So apparently 10W is not enough to charge, but it’s still at least keeping the battery from draining.
A 20w charger will definitely charge the MacBook, just slowly.
Coincidentally, the USB-C spec is written such that wattage implies a minimum set of supported voltages:
* ≤15W charger: must have 5V
* ≤27W charger: must have 5V & 9V
* ≤45W charger: must have 5V & 9V & 15V
* (OT but worth noting: >60W: requires "chipped" cable.)
* ≤100W charger: must have 5V & 9V & 15V & 20V
(levels above this starting to become relevant for the new 240W stuff)
(36W/12V doesn't exist anymore in PD 3.0. There seems to be a pattern with 140W @ 28V now, and then 240W at 48V, I haven't checked what's actually in the specs now for those, vs. what's just "herd agreement".)
Some devices are built to only charge from 20V, which means you need to buy a 45.000001W (scnr) charger to be sure it'll charge. If I remember correctly, requiring a minimum wattage to charge is permitted by the standard, so if the device requires a 46W charger it can assume it'll get 15V. Not sure about what exactly the spec says there, though.
(Of course the chargers may support higher voltages at lower power, but that'd cost money to build so they pretty much don't.)
NB: the lower voltages are all mandatory to support for higher powered chargers to be spec compliant. Some that don't do that exist — they're not spec compliant.
This has nothing to do with USB-C, this is the minimum design voltage of your lithium ion battery pack. In this case, you have a 4-cell pack, and if the cells drop below 2.895V that means they're physically f*cked and HP would like to sell you a new battery. (Sometimes that can be fixed by trickle charging, depending on how badly f*cked the battery is.)
If your laptop's USB-C circuitry were built for it, you could charge it from 5V. (Slowly, of course.) It's not even that much of a stretch given laptops are built with "NVDC"¹ power systems, and any charger input goes into a buck-boost voltage regulator anyway.
It's a 3A supply up to the 100W one, that gets upped to 5A at higher voltages.
Varying voltage power supplies are usually capped by current, not power. That's because many of the components, set maximum current and voltage that you must obey independently.
At higher voltages people start accepting higher loses in stuff like cables, because fire-safety becomes a more important concern than efficiency. So the standard relaxes things a little bit.
You're correct but it's irrelevant. My point was that these requirements are in the standard and if you want to put the USB logo on a power brick you need to meet them. And the consumer is intended to be able to rely on them - which was & still is a pretty good idea considering the USB-C cable carnage.
I wish they did something like this for USB-C cables, but it's probably too late.
They probably require higher voltages but I havent seen one myself. I usually just charge y laptop with my phone charger, what is it, 18 watts? Don't care, charges my laptop and the phone that is plugged into it overnight. Why charge at faster speeds when there is no need to
With 802.3bt type 4 (71W delivered, 90W consumed), absolutely achievable with the proper electronics, but would you trust a no-name, fly-by-night NIC to not fry your expensive devices? That's the biggest hurdle. Possibly a company like Apple, Anker, or similar megacorp or high-trust startup could pull if off.
PoE can be cheap, but usually never cheaper than non-poe. But if you have a PoE switch and spare ports, its very nice.
The problem comes when you try to design a large network and need random PoE ports on end devices where you can't home-run a cable back.
I have a Unifi Pro XG 48 PoE and I love it, but I still don't use PoE for everything. The cost of a (non unifi) poe device + the cost of using one of those ports always exceeds a simple power adapter on the other side (if possible).
Doing home automation of lamps, sensors, speakers via PoE would be great too. It should faster and more stable than Zigbee/Wifi and with no need to change the batteries often.
Too bad this is 10Gbase-T, that energy-wasting hot-running garbage needs to die sooner rather than later. Good thing the ranges for 25Gbase-T are short enough to make it impractical for home use.
(Fibre is nowhere near as "sensitive" as some people believe.)
The problem with fibre isn't the sensitivity. It's that most endpoints have a 1Gbps copper port on them and then Cat6A ports can be used with the common devices but also allow you to add or relocate 10Gbps devices without rewiring the building again.
You've been able to get Intel X520 NICs [0], with transceivers included for ~40USD on Newegg for a long time. This is a little more than double the price of Newegg's cheapest single-port 10/100/1000 copper card, but even the cheapest available such card is three times your "chicken and egg"-solving price point.
I suspect the combination of the absence of cheap-o all-in-one AP/router combo boxes with any SFP+ cages and fiber cabling's reputation of being extremely fragile have much more to do with its scarcity at the extremely low end of networking gear than anything else.
But +$15 and an extra wall outlet per endpoint is still an inconvenience, and if a two-port device with its own power supply can be made for $15 then where is the PCIe/USB to fibre adapter for <$10?
Yep. Good NICs last for approximately forever, life's way too short to deal with maybe-flaky NICs, and the price difference between the Amazon Special and something that's going to be reliable is -what- two big boxes of Cheerios? Two dozen eggs? Not. Worth it.
> But it's not competing with those, it's competing with the copper port which is already built into most devices.
Correct! That's part of why I was so very surprised to see you suggesting that extremely cheap PCI Express and USB adapters would "solve the chicken and egg problem".
> The point being you need some cheap way to plug in existing copper devices if you run fibre to the endpoints.
That's called a multi-port switch. Netgear sells five-port gigabit ones for like 20 USD. Switches that have two SFP+ cages and eight copper gigabit ports [0] are six times the price of a cheap-o Netgear switch, but are something that's going to last at least a decade. It's also pretty uncommon to find SOHO switches that have SFP+ cages and don't have at least one fixed copper port.
> This plus $5 for a transceiver is pretty close at $15:
If you're connecting a single device, why the hell would you use that when you could slap a copper SFP or SFP+ module in the switch's cage and run a cable? If you're connecting multiple devices, then either install multiple copper modules and run multiple cables, run multiple copper cables from fixed copper ports on the switch, or put a switch where the existing copper devices are.
> If you're connecting a single device, why the hell would you use that when you could slap a copper SFP or SFP+ module in the switch's cage and run a cable?
The problem to be solved is that you want to be able to put fibre inside the walls of the building instead of copper. Running a new cable to the switch closet is the thing to be prevented.
But if the wall jacks are fibre then you need some economical way of hooking them up to every printer and single-purpose device with a network port. If you have to buy another $100+ switch just to get from fibre to copper even when there is only one device near that jack, people aren't going to go for that.
> The problem to be solved is that you want to be able to put fibre inside the walls of the building instead of copper. Running a new cable to the switch closet is the thing to be prevented.
...why would you ever not run copper alongside fiber for new construction? If nothing else, PoE is extremely useful, and nothing says that you actually have to connect all of that copper cable to your switch... you can connect it as-needed. I also can't imagine that most refits only have room for exactly one cable in their conduit. [0]
I'd expect to hear the sort of plan you propose from a PHB or Highly Paid Consultant, not someone who actually has had to use that sort of configuration.
Regardless, the scenario you're now proposing is one where noone other than a PHB would use that Amazon Special that you linked for media conversion.
[0] If there's no conduit and cables are all flopping around in the wall, then there's even more room for cabling.
The original problem was that everyone runs copper instead of fibre because there are too many existing devices that only have copper. Running both everywhere would require you to buy and terminate twice as much cable as you expect to use, which leads people to running only copper again.
If you chose PCs to begin with that come with fibre ethernet or put quality cards in the ones that matter then you could make fibre the default instead of copper. Until you have a number of devices like printers or VoIP phones or Raspberry Pis that have no need for 10Gbps or even 1Gbps connectivity, they just need a way to be plugged in at all. If you need to add $100+ in conversion expense to each of those devices, you're back to using copper by default.
> Running both everywhere would require you to buy and terminate twice as much cable as you expect to use...
Ah. Let's play with that logic a bit:
"Running Ethernet cabling everywhere would require you to buy and terminate far more than twice as much cable as you expect to use. Just run power cables and wire up one extra outlet for a HomePlug in each room.".
Yeah, that checks out. "Powerline Ethernet" devices are actually pretty good these days, and are right around your magic price range... Amazon has them at ~13 USD per unit. [0] Why would anyone bother running a second cable to each room? Thirteen bucks per room has to be way less than the materials and labor cost for the cable run. Doing anything else is, like, really stupid. Don't you agree?
Anyway. You expect to use the cabling that you plan to install... plus some extra for screwups, man.
Which is why people run only copper because that costs less than running multiple types of cable everywhere when most drops only have one device, and then pull fibre through using the existing copper cable in the rare instances where they find a need for 40Gbps or more.
But then the copper gets used for 10Gbps connections instead of fibre because it's what's already in the building.
> You can run composite cable if you desire copper, fiber and power.
Oooh. Cool.
By "power" do you mean 120/240VAC, or do you mean much lower voltage DC? I've found some Belden cabling that I think provides mains power and Ethernet, and I've found fiber cabling that I guess carries lower voltage DC, but am having a tough time finding a cable that combines fiber and copper data with mains power. Do you have an example of such a cable handy?
(Full disclosure: I'm refusing to spend more than like five minutes on the search... so I might have been able to dig up examples of such a cable.)
Ymmv. I've got a mix of cheap premade patch cables and some I crimped from solid core, all cat5e, all holding 10gbe totally happily. I suspect that only works because they're a meter or two long but that reaches across the rack.
It's inherently worse than anything fibre, or even DAC cables (which are kinda cheating.) It needs a shitton of analog "magic" to work with the bandwidth limitations of copper cabling.
DAC cables are cheating because due to the extremely short range limits (5m, 7m if you're very lucky) they can just put the 10Gbase-R/SFI signal straight on a pair of Copper at 10.3125 Gbaud.
10Gbase-T, to try to get to 100m, throws FEC on it and converts the signal to 4x PAM-16/THP at 800 Mbd, and then uses 4 copper pairs *bidirectionally*. That's the analog magic.
Okay. Sure. But why do we notice that on 10GbaseT and on 1? Is there some signal processing which is exponentially expensive at faster speeds? I’ve seen cards using 25W per port.
Yes, that signal processing is massively more expensive. A 10Gbase-T PHY is a sophisticated DSP. Not sure if the power needs are exponential, given we only have a few data points, but it's in the ballpark.
(1000base-T PHYs are already DSPs, but nowhere near as sophisticated)
"Card supports 10Gbit/s and 10/100/1000/2500/5000/10000Mbit/s Ethernet"
Nice to see; some NICs are shedding 10/100 support. Apparently, it's not necessary to do this, even in a low cost device.
100BASE-TX uses just two pairs (lanes), one for sending and one for receiving. 1000BASE-T uses all four pairs, for both sending and receiving. Therefore, a 100BASE-TX interface that's only receiving needs to power up one pair. A 1000BASE-T interface needs to power all four pairs all the time.
I recall reading about some extensions that allow switching off some of the pairs some of the time ("Green Ethernet"), but I think that they require support on both sides of the link, and I'm not sure if they are widely deployed.
10M is even simpler, to the point that even a fast MCU can bit-bang it.
The dedicated machine I still keep around for Windows things has two onboard 2.5GbE ports. It will apparently sometimes, even with all power saving features turned off, randomly negotiate down to 100 mbit if I leave the machine alone for a bit, and then stay at that speed forever unless I manually reset the link after wondering why transferring large amounts of data is bottlenecking severely.
The cable was chewed through by cats, so perhaps it was three just in that moment.
The connection was overall unreliable, so I guess it must have been four, just not all of the time.
Ah, the old Cat-3 cable. Been there.
It's not, cf. sibling posts. The GP probably learned networking in the 80ies~90ies when it was true, but those times are long gone.
(unless you're talking wifi.)
For regular Ethernet, the switch will have a table of which IPs are on which NIC and thus can dynamically send packets at the right transmission protocols supported by those NICs without degrading the service of other NICs.
100m is fine. 10m is fine but I can’t think of anything that negotiates 10m other than maybe WOL (I don’t use it enough to be sure from memory).
If I didn ahve something esoteric it would be on a specialised vlan anyway.
If this is the same adapter in a different housing, will it also be limited to 7Gbps?
[0]: https://global.icydock.com/product_247.html
It is probably the speed of it being read into RAM.
Try entering sync right after copying to see how long it really takes
It beats my previous desktop's RAM speed, what a time to live in.
Of course, just give them some time and they'll come up with USB4 "gen classic" at 11 Mbps.
https://www.aliexpress.com/item/1005008555989592.html
I have one of these, though I'm using with a USB 3.x port as that's what my desktop has. For me it's working fine, and for others with actual USB 4 ports it seems to be working properly for them.
Interestingly it seems to get burning hot on the MacBook M1 Pro while it remains cool on the M5 Pro model.
Maybe the workload is different, but I would not rule out some sort of hardware or driver difference. I only use a 1G port on my router at the moment.
I am definitely not the person to shed any light on what is going on, but you've added to my feeling that these adapters are all incomprehensible, so I'll try and do the same for you.
I have a USB C ethernet adapter (a Belkin USB-C to Ethernet + Charge Adapter which I recommend if you need it). I ran out of USB C ports one day, and plugged it through a USB C to USB A adapter instead. I must have done an fast.com speed-test to make sure it wasn't going to slow things down drastically, and found that the latency was lower! Not a huge amount, and I think the max speed was quicker without the adapter. But still, lower latency through a $1.50 Essager USB C to USB A adapter, bought from Shein or Shopee or somewhere silly!
I tried tons of times, back and forward, with the adapter a few times, then without the adapter a few times. Even on multiple laptops. As much as I don't want to, I keep seeing lower latency through this cheap adapter.
Next step, I'll try USB C to USB A, then back through a USB A to USB C adapter. Who knows how fast my internet could be!
If anyone's aware of something better, I'd be interested too :)
(Then again I wouldn't voluntarily use 5Gb-T or 10Gb-T anyway, and ≈50W is enough for most use cases.)
[ed.: https://www.aliexpress.us/item/3256807960919319.html ("2.5GPD2CBT-20V" variant) - actually 2.5G not 1G as I wrote initially]
A lot of laptops won't accept less than 60w
My work laptop won't accept less than 90w (A modern HP, i7 155h with a random low end GPU)
At first everyone at the office just assumed that the USB C wasn't able to charge the pc
When plugged into 100W chargers while powered on, it takes ten minutes to gain a single percentage point. Idle in power save may let me charge the thing in a few hours. If I start playing video, the battery slowly drains.
If your laptop is part space heater, like most laptops with Nvidia GPUs in them seem to be, using a low power adapter like that is pretty useless.
Also, 100W chargers are what, 25 euros these days? An OEM charger costs about 120 so the USB-C plan still works out.
Other manufacturers do similar things. Apple accepts lower wattage chargers (because that's what they sell themselves) but they ignore two power negotiation standards and only supports the very latest, which isn't in many affordable chargers, limiting the fast charge capacity for third parties.
Some devices expect USB-A on the charger side instead of C
USB-A pump out 1A5V(5W) regardless of what's connected to it, then it negotiate higher power if available.
USB C-C does not give any power if the receiving device is not able to negotiate it
I can’t recall which cable I used though. The cable might have been garbage but I’m pretty sure I threw out all the older USB cables so they wouldn’t get mixed with more modern supporting cables.
A 20w charger will definitely charge the MacBook, just slowly.
Mine under very rarely exceeds 10w.
* ≤15W charger: must have 5V
* ≤27W charger: must have 5V & 9V
* ≤45W charger: must have 5V & 9V & 15V
* (OT but worth noting: >60W: requires "chipped" cable.)
* ≤100W charger: must have 5V & 9V & 15V & 20V
(levels above this starting to become relevant for the new 240W stuff)
(36W/12V doesn't exist anymore in PD 3.0. There seems to be a pattern with 140W @ 28V now, and then 240W at 48V, I haven't checked what's actually in the specs now for those, vs. what's just "herd agreement".)
Some devices are built to only charge from 20V, which means you need to buy a 45.000001W (scnr) charger to be sure it'll charge. If I remember correctly, requiring a minimum wattage to charge is permitted by the standard, so if the device requires a 46W charger it can assume it'll get 15V. Not sure about what exactly the spec says there, though.
(Of course the chargers may support higher voltages at lower power, but that'd cost money to build so they pretty much don't.)
NB: the lower voltages are all mandatory to support for higher powered chargers to be spec compliant. Some that don't do that exist — they're not spec compliant.
I guess that would be out of spec then?
edit: nvm I didn't see the qualifier 'minimum'
If your laptop's USB-C circuitry were built for it, you could charge it from 5V. (Slowly, of course.) It's not even that much of a stretch given laptops are built with "NVDC"¹ power systems, and any charger input goes into a buck-boost voltage regulator anyway.
¹ google "NVDC power", e.g. https://www.monolithicpower.com/en/learning/resources/batter... (scroll down to it)
Varying voltage power supplies are usually capped by current, not power. That's because many of the components, set maximum current and voltage that you must obey independently.
At higher voltages people start accepting higher loses in stuff like cables, because fire-safety becomes a more important concern than efficiency. So the standard relaxes things a little bit.
I wish they did something like this for USB-C cables, but it's probably too late.
Laptop charges fine regular 5V as well.
Might be a struggle I suspect!
The problem comes when you try to design a large network and need random PoE ports on end devices where you can't home-run a cable back.
I have a Unifi Pro XG 48 PoE and I love it, but I still don't use PoE for everything. The cost of a (non unifi) poe device + the cost of using one of those ports always exceeds a simple power adapter on the other side (if possible).
I think about this a lot.
https://hackaday.com/2023/08/14/adding-power-over-ethernet-s...
Makes sense, thanks!
Surely a matter of time until someone does this…
https://www.procetpoe.com/poe-usb-converter/ (some of these are power-only)
https://shop.poetexas.com/products/gbt-usbc-pd-usbc?variant=...
65W 802.3bt and gigabit Ethernet out on the same PD cable.
Also a crude fixed hub for data and a keyboard and mouse for docking laptops:
https://shop.poetexas.com/products/bt-usbc-a-pd?variant=3938...
(Fibre is nowhere near as "sensitive" as some people believe.)
What probably would is something like having PCIe and USB to 1Gbps fiber adapters that cost $5.
I suspect the combination of the absence of cheap-o all-in-one AP/router combo boxes with any SFP+ cages and fiber cabling's reputation of being extremely fragile have much more to do with its scarcity at the extremely low end of networking gear than anything else.
[0] This is a two-port SFP+ PCI Express card
https://www.amazon.com/1000Mbps-Network-Performance-Gigabit-...
https://www.amazon.com/SALAN-Ethernet-Portable-Internet-Conv...
But it's not competing with those, it's competing with the copper port which is already built into most devices.
Another thing that would work is something like this (also $5.99), but with one of the ports as fibre:
https://www.amazon.com/Gigabit-Ethernet-Splitter-1000Mbps-In...
The point being you need some cheap way to plug in existing copper devices if you run fibre to the endpoints.
This plus $5 for a transceiver is pretty close at $15:
https://www.amazon.com/Gigabit-Ethernet-Converter-Auto-Negot...
But +$15 and an extra wall outlet per endpoint is still an inconvenience, and if a two-port device with its own power supply can be made for $15 then where is the PCIe/USB to fibre adapter for <$10?
Yep. Good NICs last for approximately forever, life's way too short to deal with maybe-flaky NICs, and the price difference between the Amazon Special and something that's going to be reliable is -what- two big boxes of Cheerios? Two dozen eggs? Not. Worth it.
> But it's not competing with those, it's competing with the copper port which is already built into most devices.
Correct! That's part of why I was so very surprised to see you suggesting that extremely cheap PCI Express and USB adapters would "solve the chicken and egg problem".
> The point being you need some cheap way to plug in existing copper devices if you run fibre to the endpoints.
That's called a multi-port switch. Netgear sells five-port gigabit ones for like 20 USD. Switches that have two SFP+ cages and eight copper gigabit ports [0] are six times the price of a cheap-o Netgear switch, but are something that's going to last at least a decade. It's also pretty uncommon to find SOHO switches that have SFP+ cages and don't have at least one fixed copper port.
> This plus $5 for a transceiver is pretty close at $15:
If you're connecting a single device, why the hell would you use that when you could slap a copper SFP or SFP+ module in the switch's cage and run a cable? If you're connecting multiple devices, then either install multiple copper modules and run multiple cables, run multiple copper cables from fixed copper ports on the switch, or put a switch where the existing copper devices are.
[0] <https://mikrotik.com/product/css610_8g_2s_in>
The problem to be solved is that you want to be able to put fibre inside the walls of the building instead of copper. Running a new cable to the switch closet is the thing to be prevented.
But if the wall jacks are fibre then you need some economical way of hooking them up to every printer and single-purpose device with a network port. If you have to buy another $100+ switch just to get from fibre to copper even when there is only one device near that jack, people aren't going to go for that.
...why would you ever not run copper alongside fiber for new construction? If nothing else, PoE is extremely useful, and nothing says that you actually have to connect all of that copper cable to your switch... you can connect it as-needed. I also can't imagine that most refits only have room for exactly one cable in their conduit. [0]
I'd expect to hear the sort of plan you propose from a PHB or Highly Paid Consultant, not someone who actually has had to use that sort of configuration.
Regardless, the scenario you're now proposing is one where noone other than a PHB would use that Amazon Special that you linked for media conversion.
[0] If there's no conduit and cables are all flopping around in the wall, then there's even more room for cabling.
If you chose PCs to begin with that come with fibre ethernet or put quality cards in the ones that matter then you could make fibre the default instead of copper. Until you have a number of devices like printers or VoIP phones or Raspberry Pis that have no need for 10Gbps or even 1Gbps connectivity, they just need a way to be plugged in at all. If you need to add $100+ in conversion expense to each of those devices, you're back to using copper by default.
Ah. Let's play with that logic a bit:
"Running Ethernet cabling everywhere would require you to buy and terminate far more than twice as much cable as you expect to use. Just run power cables and wire up one extra outlet for a HomePlug in each room.".
Yeah, that checks out. "Powerline Ethernet" devices are actually pretty good these days, and are right around your magic price range... Amazon has them at ~13 USD per unit. [0] Why would anyone bother running a second cable to each room? Thirteen bucks per room has to be way less than the materials and labor cost for the cable run. Doing anything else is, like, really stupid. Don't you agree?
Anyway. You expect to use the cabling that you plan to install... plus some extra for screwups, man.
[0] <https://www.amazon.com/Linksys-PLEK500-Homeplug-AV2-Powerlin...>
But then the copper gets used for 10Gbps connections instead of fibre because it's what's already in the building.
Oooh. Cool.
By "power" do you mean 120/240VAC, or do you mean much lower voltage DC? I've found some Belden cabling that I think provides mains power and Ethernet, and I've found fiber cabling that I guess carries lower voltage DC, but am having a tough time finding a cable that combines fiber and copper data with mains power. Do you have an example of such a cable handy?
(Full disclosure: I'm refusing to spend more than like five minutes on the search... so I might have been able to dig up examples of such a cable.)
To be fair, the power consumption is also my biggest gripe with my WiFi 6 AP, they run extremely hot.
10Gbase-T, to try to get to 100m, throws FEC on it and converts the signal to 4x PAM-16/THP at 800 Mbd, and then uses 4 copper pairs *bidirectionally*. That's the analog magic.
Yes, that signal processing is massively more expensive. A 10Gbase-T PHY is a sophisticated DSP. Not sure if the power needs are exponential, given we only have a few data points, but it's in the ballpark.
(1000base-T PHYs are already DSPs, but nowhere near as sophisticated)
Anyone who talks about 25GBASE-T like it actually exists, doesn't know anything about what they're talking about.
40Gbase-T will never exist, sure. 25Gbase-T very likely will.