[HN Gopher] Reliable 25 Gigabit Ethernet via Thunderbolt
       ___________________________________________________________________
        
       Reliable 25 Gigabit Ethernet via Thunderbolt
        
       Author : kohlschuetter
       Score  : 183 points
       Date   : 2026-01-27 20:57 UTC (5 days ago)
        
 (HTM) web link (kohlschuetter.github.io)
 (TXT) w3m dump (kohlschuetter.github.io)
        
       | cs02rm0 wrote:
       | Now I just have to contrive the circumstances where this is
       | useful to me. :)
        
         | e40 wrote:
         | Porn?
        
           | leosanchez wrote:
           | What kind of porn requires 25 gigabits ?
        
             | LeoPanthera wrote:
             | A _lot_ of porn.
        
             | modderation wrote:
             | As a guess, large-scale volumetric or photogrammetric
             | "datasets" could be difficult to stream over lesser
             | interconnects.
        
             | AdrianB1 wrote:
             | Mind-blowing 3D stereoscopic 480 FPS with 11.2 audio
             | channels with 768 kbps rate and spatial sound stage :D
        
         | mcny wrote:
         | I don't know about the Ethernet part but it bothers me that
         | even wifi has become faster than the wired USB port on our
         | phones.
         | 
         | All I want to do is copy over all the photos and videos from my
         | phone to my computer but I have to baby sit the process and
         | think whether I want to skip or retry a failed copy. And it is
         | so slow. USB 2.0 slow. I guess everybody has given up on the
         | idea of saving their photos and videos over USB?
        
           | diogocp wrote:
           | > USB 2.0 slow
           | 
           | Many phones indeed only support USB 2.0. For example the base
           | iPhone 17. The Pro does support USB 3.2, however.
           | 
           | > I guess everybody has given up on the idea of saving their
           | photos and videos over USB?
           | 
           | Correct.
        
           | ranguna wrote:
           | Why don't you get a phone with 3.0+ USB?
           | 
           | My last two phones in the last 4 years had at least USB 3.1
        
           | jacquesm wrote:
           | Wifi is fast but the latency is terrible and the reliability
           | is even worse. It can go up and down like a yo-yo. USB is far
           | more predictable even if it is a bit slower.
        
             | rbanffy wrote:
             | I have a cluster of 4 RPi Zero Ws and network reliability
             | is not great. Since it is for the chaos, it's fine, but
             | it's very common to have a node be offline at any given
             | time.
             | 
             | Even worse, the control plane is exposed, but for something
             | that runs 3 Hercules mainframe emulation and two Altairs
             | with MP/M, it's fine.
        
               | jacquesm wrote:
               | I have a bunch of HA wifi connected sensors, I see them
               | drop off and reconnect all the time it is most annoying.
        
               | AdrianB1 wrote:
               | Not sure why this happens to you. I have HA with several
               | dozens WiFi devices and I have only 2 devices (one relay,
               | one sensor) that disconnect regularly, they have both
               | poor WiFi signal, one in a basement and one far from the
               | AP. Almost all are on 2.4 GHz, not by choice, but they
               | work well.
        
           | cirrusfan wrote:
           | > but I have to baby sit the process and think whether I want
           | to skip or retry a failed copy
           | 
           | Do you import originals or do you have the "most compatible"
           | setting turned on?
           | 
           | I always assumed apple simply hated people that use
           | windows/linux desktops so the occasional broken file was
           | caused by the driver being sort-of working and if people
           | complain, well, they can fuck off and pay for icloud or a
           | mac. After upgrading to 15 pro which has 10 gbps usb-c it
           | still took forever to import photos and the occasional broken
           | photos kept happening, and after some research it turns out
           | that the speed was limited by the phone converting the .heic
           | originals into .jpg when transferring to a desktop. Not only
           | does it limit the speed, it also degrades the quality of the
           | photos and deletes a bunch of metadata.
           | 
           | After changing the setting to export original files the
           | transfer is much faster and I haven't had a single broken
           | file / video. The files are also higher quality and lower
           | filesize, although .heic is fairly computationally-demanding.
           | 
           | Idk about Android but I suspect it might have a similar
           | behavior
        
           | walterbell wrote:
           | _> given up on the idea of saving their photos and videos
           | over USB?_
           | 
           | Until USB has monthly service business to compete with cloud
           | storage revenue.
        
           | drawfloat wrote:
           | I feel like this is an artifact from the late 2010s when the
           | talk was of removing the port completely from phones, where
           | that was being touted alongside swapping speakers with haptic
           | screen audio as a way to make them completely waterproof.
           | 
           | As wireless charging never quite reached the level hoped -
           | see AirPower - and Google/Apple seemingly bought and never
           | did anything with a bunch of haptic audio startups, I figure
           | that idea died....but they never cared enough to make sure
           | the USB port remained top end.
        
             | fc417fc802 wrote:
             | I'd usually be against losing ports and user serviceable
             | stuff but if the device could actually be properly sealed
             | up (ie no speakers, mics, charge ports, etc) that would be
             | legitimately useful.
        
           | rbanffy wrote:
           | If the photos on the phone are visible as files on a mounted
           | filesystem, you can use rsync to copy them. If the connection
           | drops but recovers by itself, you can put rsync inside a
           | while true loop until it's doing nothing.
           | 
           | I'm using Dropbox for syncing photos from phone to Linux
           | laptop, and mounting the SDcard locally for cameras, so this
           | is a guess.
        
         | rbanffy wrote:
         | Wouldn't this be useful for clustering Macs over TB5? Wasn't
         | the maximum bandwidth over USB-cables 5Gbps? With a switch, you
         | could cluster more than just 4 Mac Studios and have a couple
         | terabytes for very large models to work with.
        
           | kohlschuetter wrote:
           | I was hoping somebody would suggest that (and eventually try
           | it out).
           | 
           | With TB5, and deep pockets, you might probably also benchmark
           | it against a setup with dedicated TB5 enclosures (e.g.,
           | Mercury Helios 5S).
           | 
           | TB5 has PCIe 4.0 x4 instead of PCIe 3.0 x4 -- that should
           | give you 50 GbE half-duplex instead of 25 GbE. You would need
           | a different network card though (ConnectX-5, for example).
           | 
           | Pragmatically though, you could also aggregate (bond)
           | multiple 25 GbE network card ports (with Mac Studio, you have
           | up to 6 Thunderbolt buses, so more than enough to saturate a
           | 100GbE connection).
        
             | rbanffy wrote:
             | Too bad Jeff Geerling returned his Mac Studios to Apple.
             | Would be lovely to see how 5x faster RDMA impacts the
             | performance.
        
               | geerlingguy wrote:
               | 25 Gbps isn't all that much. It would be good, but would
               | be below the 40+ Gbps I was getting on the TB5 ring
               | network.
               | 
               | I think where it would show more significant speed up is
               | on the AMD Strix Halo cluster.
               | 
               | Except I haven't been able to get RDMA over Thunderbolt
               | on there to work, so it'd be apples to oranges comparing
               | ConnectX to Thunderbolt on Linux.
        
         | kohlschuetter wrote:
         | Remote Time Machine backups are snappier than ever before :)
        
         | notrustincloud wrote:
         | rsync...grsync...a solution for broken partial batch transfers
         | since forever
        
         | sschueller wrote:
         | Would be useful if I had to debug my internet link and I only
         | had a laptop.
        
           | kohlschuetter wrote:
           | It also works on iPad Pro :)
        
         | consp wrote:
         | I recently did a complete disk backup/clone which only took 15
         | minutes instead of hours. Maxed the SSD which was being backed
         | up at about 2.5GB/s.
        
         | soneil wrote:
         | Pretty much anywhere you have networked storage? Gigabit is
         | about on-par with pre-sata ATA133.
        
       | userbinator wrote:
       | Thunderbolt is basically external PCIe, so this is not so
       | surprising. High speed NICs do consume a relatively large amount
       | of power. I have a feeling I've seen that logo on the board
       | before.
        
         | xattt wrote:
         | The PCI-E logo or the "octopus in a chip" logo? I'm more
         | interested in the latter.
        
           | userbinator wrote:
           | The octopus logo. Might've been on Aliexpess or one of the
           | other Chinese marketplaces.
        
         | kohlschuetter wrote:
         | I don't know how to measure the direct power impact on a
         | MacBook Pro (since it's got a battery), but the typical power
         | consumption of these cards is 9 W, not much more than Aquantia
         | 10 GBit cards.
         | 
         | Also, if you remember where you saw that logo, please let me
         | know!
        
           | consp wrote:
           | Plus 1-2.5w per active cable. You need the heatsinks as the
           | cx4 cards expect active airflow, and active transceivers as
           | well.
           | 
           | I have a 10gbit dual port card in a Lenovo mini pc. There is
           | no normal way to get any heat out of there so I put a 12v
           | small radial fan in there as support. It works great at 5v:
           | silent and cool. It is a fan though so might not suit your
           | purpose.
        
             | ZenDroid wrote:
             | Do you mean active Thunderbolt cable? Short Thunderbolt
             | cables (0.8m) are passive.
             | 
             | https://www.reddit.com/r/UsbCHardware/comments/y5uokj/comme
             | n...
        
               | userbinator wrote:
               | Active Ethernet cables.
        
           | usagisushi wrote:
           | JFYI, for measuring power draw, you might be able to use
           | `macmon`[0] to see the total system power consumption. The
           | values reported by the internal current sensor seem to be
           | quite accurate.
           | 
           | [0] https://github.com/vladkens/macmon
        
             | usagisushi wrote:
             | Speaking of hardware, the RTL8159 (10Gbps) hit the market
             | late last year and is said to consume only about 2-3W. It
             | apparently runs very cool compared to older chips. (Though
             | it would need to be bonded to reach 25Gbps ;-)
        
               | kohlschuetter wrote:
               | I got me one of these adapters (RTL8127AF TXA403, with
               | SFP+ cage); I haven't properly benchmarked it yet.
               | 
               | There's no driver support on macOS, and for Linux you'd
               | need a bleeding edge kernel. Just trying to physically
               | connect it (along with a connected SFP28 transceiver) to
               | my Mac's Thunderbolt port using an external PCIe-to-TB
               | adapter, macmon tells me a power draw of around 4.3 W, so
               | it's not significantly less for half the bandwidth, but
               | the card doesn't get hot at all.
        
             | kohlschuetter wrote:
             | Very nice tip, thank you!
             | 
             | I measure around +11W idle. While running a speed test, I
             | read ca. +15W.
        
               | usagisushi wrote:
               | Thanks for the measurements! 15W under load definitely
               | justifies those massive heatsinks.
               | 
               | I'm looking forward to your writeup on the RTL8127AF as
               | well. Your blog is awesome!
        
       | zokier wrote:
       | Note that you can do point-to-point network links directly with
       | thunderbolt (and usb4).
       | 
       | https://support.apple.com/guide/mac-help/ip-thunderbolt-conn...
       | etc
        
         | kohlschuetter wrote:
         | Yes! However, I got around 15 Gbps with a Thunderbolt-only
         | setup (TB3/TB4) = only 75% of the Ethernet setup.
         | 
         | You'd also mostly be limited to short cables (1-2m) and a ring
         | topology.
        
           | admash wrote:
           | Any idea why that would be the case?
        
             | butvacuum wrote:
             | The linux implementation is quite poor. Among other issues,
             | your answer is linux treats it as a TCP/IP link- so packets
             | don't have any offloading for checksums, etc. it's also
             | incomplete (ex- you have to physically unplug and replug
             | the cord every time one side loses link- even a reboot).
             | 
             | This is my firsthand experence trying to get some tablet
             | motherboards to link up and work as a proxmox cluster w/
             | TB3 as the link between nodes.
        
               | sponaugle wrote:
               | I have a 3 node proxmox setup on MS-01s using a 25G
               | Thunderbolt ring for Ceph, and indeed it took a lot of
               | hoops to get it working correctly and reliably. I did
               | manage to get it such that nodes can go up and down
               | without needing to unplug anything, and the dynamic
               | routing works if a node disappears. Performance is pretty
               | good, with a more realistic 20ish gbit/sec.
        
       | Nextgrid wrote:
       | Neat, but the thermal design is absolutely terrible. Sticking
       | that heatsink inside the aluminum case without any air
       | circulation is awful.
        
         | kohlschuetter wrote:
         | Yeah, it's because the network card adapter's heatsink is
         | sandwiched between two PCBs. Not great, not terrible, works for
         | me.
         | 
         | The placement is mostly determined by the design of the OCP 2.0
         | connector. OCP 3.0 has a connector at the short edge of the
         | card, which allows exposing/extending the heat sink directly to
         | the outer case.
         | 
         | If somebody has the talent, designing a Thunderbolt 5 adapter
         | for OCP 3.0 cards could be a worthwhile project.
        
           | Nextgrid wrote:
           | A Flex PCB connecting the OCP2 connector would allow to put
           | the converter board _behind_ the NIC board, allowing the NIC
           | board to be exposed to the aluminum case to use the case
           | itself as a heatsink (would need a split case so the NIC
           | board can be screwed to one side of the case, pressing the
           | main chip against it via a thermal pad).
           | 
           | As a stop-gap, I'd see if there was any way to get airflow
           | _into_ the case - I 'd expect even a tiny fan would do much
           | more than those two large heatsinks stuck onto the case
           | (since the case itself has no thermal connection to the chip
           | heatsink).
        
             | kohlschuetter wrote:
             | My goal was to get a fanless setup (for a quiet office).
             | 
             | If that's not a requirement just get the Raiden Digit Light
             | One, which does have a fan (and otherwise the same network
             | card).
             | 
             | If I could design an adapter PCB myself, I would go
             | straight to OCP 3.0, which allows for a much simpler
             | construction, and TB5 speeds.
             | 
             | Alternatively, there are DELL CX422A rNDC cards (R887V)
             | that appear to have an OCP 2.0 connector but a better
             | heatsink design.
        
           | consp wrote:
           | I'd be more worried about cooling the transceivers properly.
        
             | kohlschuetter wrote:
             | My optical transceiver gets to around 52 degC (measured via
             | IR camera), well below its design limit, so that's not bad.
             | 
             | If truly concerned, one could use SFP28 to SFP28 cage
             | adapters to have the heat outside the case, and slap on
             | some extra heatsinks there.
        
       | consp wrote:
       | I'm surprised you are only getting 20gbit/s. I did not expect
       | PCIe to be be the limiting factor here. I've got a 100gbit cx4
       | card currently in a PCIe3 X4 slot (for reasons, don't judge) and
       | it easily maxes that out. I would have expected the 25g cx4 cards
       | to be at least able to get everything out of it. RDMA is required
       | to achieve that in a useful way though.
       | 
       | Edit: forgot is isn't "true" PCIe but tunneled.
        
         | kohlschuetter wrote:
         | The limitation is Thunderbolt (32 Gbps theoretical limit for
         | PCIe 3 tunneling).
        
       | otterpro wrote:
       | > reduces temperatures by at least 15 Kelvin, bringing the
       | ambient enclosure temperature below 40 degC,
       | 
       | I had to do a double-take when it mentioned Kelvin since That is
       | physically impossible.
        
         | sigio wrote:
         | reduces temperatures by at least 15 Kelvin == the same as
         | reduces temperatures by at least 15 Celcius.
         | 
         | It 'reduces it by' ... not reduces it TO
        
         | maratc wrote:
         | Isn't "reduces temperatures by 15 Kelvin" the same as "reduces
         | temperatures by 15 Celsius"?
        
           | buildbot wrote:
           | Yes, Kelvin is only a linear offset from Celsius. (273.15 for
           | anyone who doesn't already know).
           | 
           | It's a little bit funny/coy to use it mixed with Celsius.
        
       | madduci wrote:
       | I still have issues under Linux (Kernel 6.14) and Thinderboldt 4
       | docking stations. The simply don't get recognised.
       | 
       | But this is a cool solution
        
         | kohlschuetter wrote:
         | Thanks! Have you tried the boltctl/rescan setup I mentioned in
         | the post? It should get you going, as long as your
         | Thunderbolt/USB4 setup is correct.
         | 
         | If you're using an adapter card to add Thunderbolt
         | functionality, then your mainboard needs to support that, and
         | the card must be connected to a PCIe bus that's wired to the
         | Intel PCH, not to the CPU.
        
           | madduci wrote:
           | Yes, rescan, re-enroll too. But it still shows as
           | disconnected. I don't know if the firmware is completely
           | incompatible, but it is weird that under windows works and in
           | Linux doesn't
        
             | kohlschuetter wrote:
             | Disconnected as in "network"? What PCIe card do you use?
             | Can you update the firmware (maybe from Windows)?
             | 
             | Also check the BIOS settings (try setting TB security to
             | "No Security" or "User Authorization")
             | 
             | Some OEM Mellanox cards can be cross-flashed to NVIDIA's
             | stock firmware, maybe that's also relevant.
        
               | madduci wrote:
               | It's embedded in the laptop (a HP ZBook from work).
               | Disconnected as in network. Laptop charges, but signal
               | doesn't work. With Thunderbolt 3 devices, it works. (The
               | card itself is T4).
        
       | omgtehlion wrote:
       | Ha! Been running these for years on both linux and windows (on
       | lenovo x1 laptops). Using cheap chinese thunderbolt-to-nvme
       | adapters + nvme-to-pcie boards + mellanox cx4 cards (recently got
       | one cx5 and a solarflare x2).
       | 
       | Pic of a previous cx3 (10 gig on tb3) setup:
       | https://habrastorage.org/r/w780/getpro/habr/upload_files/d3c...
       | 
       | 10gig can saturate full speed, 25G in my experience rarely
       | reaches same 20G as the author observed.
        
         | kasey_junk wrote:
         | If you don't mind me asking, what are you using these for?
         | Saturating these seems like it would have reasonably few
         | workloads outside of like cdn or multi-tenant scenarios.
         | Curious what my lack of imagination is hiding here.
        
           | geerlingguy wrote:
           | I do media production, and sometimes move giant files (like
           | ggufs) around my network, so 25 Gbps is more useful than 10
           | Gbps, if it's no too expensive.
        
           | omgtehlion wrote:
           | Officially: to access NAS, get raw market-data files (tens to
           | hundreds of gigabytes a day), not needed on laptop every day,
           | but only once in a while to fix or analyze something.
           | 
           | Really: because I can, and it is fun. I upgraded my home lan
           | to 10G, because used 10G hardware is cheap (and now 25G
           | enters the same price range).
        
             | sponaugle wrote:
             | "because I can, and it is fun." The best answer! I am most
             | of the way done with upgrading most of my homelab to 100G
             | from 10G, but there really isn't a practical reason for it.
             | 100G has dropped in price so much as datacenters are all
             | about 400/800G now.
        
               | omgtehlion wrote:
               | Nice! Cool to hear from a fellow admirer of overkill-lan
               | setups ;)
               | 
               | Which cards do you prefer for 100G, and what is the
               | situation with dacs/optics?
        
       | throwaway2037 wrote:
       | This is an outstanding blog post. Initially, the title did little
       | to captivate me, but the blog post was so well written that I got
       | nerd-sniped. Who knew this little adapter was so fascinating! I
       | wonder if the manufacturer is buying the Mellanox cards used from
       | data center tear-downs. The author claims they can be had for
       | only 20 USD online. That seems too good to be true!
       | 
       | Small thing: I just checked Amazon.com:
       | https://www.amazon.com/s?k=thunderbolt+25G&crid=2RHL4ZJL96Z9...
       | 
       | I cannot find anything for less than 285 USD. The blog post gave
       | a price of 174 USD. I have no reason to disbelieve the author,
       | but a bummer to see the current price is 110 USD more!
        
         | kohlschuetter wrote:
         | Thank you!
         | 
         | I think, tragically, the blog post has caused this price
         | increase.
         | 
         | The offers on Amazon are most likely all drop shippers trying
         | to gauge a price that works for them.
         | 
         | You might have better luck ordering directly from China for a
         | fraction of the price:
         | https://detail.1688.com/offer/836680468489.html
        
         | geerlingguy wrote:
         | I saw the blog post last week and immediately bought the last
         | one on that Amazon listing for the original price... hopefully
         | they restock soon!
         | 
         | I'm going to try a couple other fan assisted cooling options,
         | as I'd like to keep the setup reasonably compact.
         | 
         | I just ran fiber to my desk and I have a more expensive QNAP
         | unit that does 10G SFP+, but this will let me max out the
         | connection to my NAS.
        
           | kohlschuetter wrote:
           | Be sure to test this adapter on iPad Pro, just for kicks (yes
           | it works!)
           | 
           | Although I managed to panic the kernel a couple of times
           | without the extra heatsinks on...
        
         | buildbot wrote:
         | I believe the author is talking about the OCP (2.0) network
         | card itself, that these adapters internally. The OCP nics are
         | quite cheap compared to pcie - here's 100GBE for 100!
         | https://ebay.us/m/HMQAph
        
           | kohlschuetter wrote:
           | This 100GbE card is an OCP 2.0 type 2 adapter, which will
           | _probably_ not work with the PX PCB since that NIC has two of
           | these mezzanine connectors, and PX only one.
           | 
           | What also may not work are Dell rNDC cards. They look like
           | they have OCP 2.0 type 1 connectors, but may not quite fit
           | (please correct me if I'm wrong). They do however have a nice
           | cooling solution, which could be retrofitted to one of the
           | OCP 2.0 cards.
           | 
           | I've also ordered a Chelsio T6225-OCP cards out of curiosity.
           | These should fit in the PX adapter but require a 3rd-party
           | driver on macOS (which then supports jumbo frames, etc.)
           | 
           | What also fits physically is a Broadcom BCM957304M3040C, but
           | there are no drivers on macOS, and I couldn't get the
           | firmware updated on Linux either.
        
             | buildbot wrote:
             | That's a good point to note! I think the stacking height
             | would matter, but in theory the single connector is still
             | 8x pcie and should link without the upper 8x lanes
             | connected.
             | 
             | Spec for reference, I'm not 100% sure.
             | https://docs.nvidia.com/nvidia-connectx-5-ethernet-
             | adapter-c...
        
           | Palomides wrote:
           | you can get a 100Gb normal pcie card like a MCX416A for less
           | than $100 if you're willing to flash them
        
         | nunez wrote:
         | $285 is still an AMAZING price for 25GbE ethernet over TB4. I
         | paid $200 for the Sonnet TB4 10GbE adapter.
        
         | hardwaresofton wrote:
         | Not much to add here but wanted to agree, this is post was
         | actually hacker news (tm)
        
         | Lammy wrote:
         | > The author claims they can be had for only 20 USD online.
         | That seems too good to be true!
         | 
         | In my experience, the cheap eBay MLX cards are DellEMC/HPE/etc
         | OEM cards. However I also encountered zero problems cross-
         | flashing those cards back to generic Mellanox firmware. I'm
         | running several of those cross-flashed CX-4 Lx cards going on
         | six or seven years now and they've been totally bulletproof.
        
       | project2501a wrote:
       | nitpicking but why would someone type `sudo su` vs `sudo -i`
        
         | Bjartr wrote:
         | I've mostly only ever seen `sudo su` in tutorials, so someone
         | who's only familiar with the command through those is one
         | possible reason why.
        
         | flounder3 wrote:
         | Muscle memory for folks who have been doing it since before -i
         | was an option. I still instinctively type `sudo su -` because
         | it worked consistently on older deployments. When you have to
         | operate a fleet of varying ages and distributions, you tend to
         | quickly learn [if only out of frustration] what works
         | everywhere vs only on the newer stuff.
         | 
         | `sudo su - <user>` also seems easier for me to type than `sudo
         | -i -u <user>`
        
       | thadk wrote:
       | Does this manufacturer's practice pattern of repackaging data
       | center components (e.g. Mellanox) imply any up and coming product
       | creation opportunities?
        
       | drnick1 wrote:
       | I used to have an SFP28 Mellanox card in my home server, but went
       | back to a simple 2.5G Ethernet port for the LAN side. The
       | Mellanox card ran hot and needed an extra fan near it to
       | dissipate the heat. It was cool but there was no real benefit
       | other than occasionally when transferring some large files.
       | 
       | Until motherboards include SFP ports it's probably not worth the
       | effort at all in home setting; external adaptors like the one
       | presented here are unreliable and add several ms of latency.
        
         | kohlschuetter wrote:
         | For reference, I'm seeing pings from my Mac to my Linux boxes
         | (Lenovo Tiny5) at well under 1ms, not much worse than between
         | them directly. But yeah, your mileage may vary.
        
         | omgtehlion wrote:
         | Yep, these cards need a fan (or any kind of directed air flow).
         | 
         | Where did you get "several ms of latency" figure from? I have
         | not measured external card, but may be I should do it...
         | Because cards themselves have latency in range of microseconds,
         | not millis.
        
           | drnick1 wrote:
           | I haven't tested this particular Thunderbolt SFP adapter, but
           | my experience with a TP-Link 1Gbps USB adapter is that it
           | adds about 4ms of latency. Far from being unusable and
           | similar to WiFi perhaps, but worse than PCIe cards that
           | should be <1ms.
        
             | serf wrote:
             | it's all just driver/options crap if I were to take a
             | guess.
             | 
             | there are a lot of usb options that matter, and tp-link
             | ships lots of realtek chipsets that require very special
             | driver incantations that a lot of the linux drivers simply
             | don't replicate.
             | 
             | two+ layers of bad options will surely add 4ms quick.
        
         | throw0101c wrote:
         | > _Until motherboards include SFP ports_ [...]
         | 
         | A micro-ATX motherboard with on-board 2xSFP28 (Intel E810):
         | 
         | *
         | https://download-2.msi.com/archive/mnu_exe/server/D3052-data...
         | 
         | * https://www.techradar.com/pro/this-amd-motherboard-has-a-
         | uni...
        
       | shantara wrote:
       | That is really cool to read. And here I am, still running my home
       | network on a measly 1Gbit Ethernet. I considered upgrading, but
       | the equipment power consumption even when idle makes it an
       | expensive proposition to consider just for fun.
        
       | whatever1 wrote:
       | Any idea why ethernet stagnated in terms of speed? There was a
       | time it was so much faster compared to usb. Now even wifi seems
       | to be faster.
       | 
       | Sure one can buy nice ethernet cards and cables, but the reality
       | is that if you grab a random laptop/desktop from best buy and a
       | cable, you are looking at best at a 2.5Gb/s speed.
        
         | fulafel wrote:
         | Wireless happened, I'd think. People started using wifi and
         | cellular data for everything, so applications had to adapt to
         | this lowest common denominator, and consumer broadband demand
         | for faster-than-wifi speeds isn't there. Plus operators put all
         | their money into cellular infra leaving no money to update
         | broadband infra.
        
           | Gigachad wrote:
           | Wifi now can pretty realistically beat 2.5gbit/s while most
           | Ethernet is still gigabit. It just seems strange to live in a
           | world where the average laptop will get a faster connection
           | speed over wifi than plugged in to Ethernet.
        
         | mschuster91 wrote:
         | > Any idea why ethernet stagnated in terms of speed? There was
         | a time it was so much faster compared to usb. Now even wifi
         | seems to be faster.
         | 
         | Practically spoken, a lot of the transfer speed advertised by
         | wifi is marketing hogwash barely backed by reality, especially
         | in congested environments.
         | 
         | > Sure one can buy nice ethernet cards and cables, but the
         | reality is that if you grab a random laptop/desktop from best
         | buy and a cable, you are looking at best at a 2.5Gb/s speed.
         | 
         | For both laptops and desktops, PCI lanes. Intel doesn't provide
         | many lanes, so manufacturers don't want to waste valuable lanes
         | permanently for capabilities most people don't ever need.
         | 
         | For laptops in particular, power draw. The faster you push
         | copper, the more power you need. And laptops have even less
         | PCIe lanes available to waste.
         | 
         | For desktops, it's a question of market demand. Again - most
         | applications don't need ultra high transfer rate, most
         | household connectivity is DSL and (G)PON so 1 GBit/s is enough
         | to max out the uplink. And those few users that do need higher
         | transfer rates can always install a PCIe card, especially as
         | there is a multitude of different options to provide high
         | bandwidth connectivity.
        
         | kohlschuetter wrote:
         | The new low-power Realtek chipsets will definitely push 10 GbE
         | forward because the chipset won't be much more expensive to
         | integrate and run than the 2.5Gbps packages.
         | 
         | It all comes down to performance per Watt, the availability of
         | cheap switching gear, and the actual utility in an office /
         | home environment.
         | 
         | For 10 Gbps, cabling can be an issue. Existing "RJ45"-style Cat
         | 6 cables could still work, but maybe not all of them.
         | 
         | Higher speeds will most likely demand a switch to fiber (for
         | anything longer than a few meters) or Twinax DAC (for inter-
         | device connects). Since Wifi already provides higher speeds,
         | one may be inclined to upgrade just for that (because at some
         | point, Wireless becomes Wired, too).
         | 
         | That change comes with the complexity of running new cabling,
         | fiber splicing, worrying about different connectors (SFP+,
         | SFP28, SFP56, QSFP28, ...), incompatible transceiver
         | certifications, vendor lock-in, etc. Not a problem in the
         | datacenter, but try to explain this to a layman.
         | 
         | Lastly, without a faster pipe to the Internet, what can you do
         | other than NAS and AI? The computers will still get faster
         | chips but most folks won't be able to make use of the bandwidth
         | because they're still stuck on 1Gbps Internet or less.
         | 
         | But that will change. Swiss Init7 has shown that 25GBps
         | Internet at home is not only feasible but also affordable, and
         | China seems to be adding lots of 10G, and fiber in general.
         | 
         | Fun times ahead.
        
         | matt-p wrote:
         | We have 400Gbe which is certainly faster than USB.. but;
         | 
         | On consumer devices, I think part of the issue is that we're
         | still wedded to four-pair twisted copper as the physical
         | medium. That worked well for Gigabit Ethernet, but once you
         | push to 5 or 10 Gb/s it becomes inherently expensive. Twisted
         | pair is simply a poor medium at those data rates, so you end up
         | needing a large amount of complex silicon to compensate for
         | attenuation, crosstalk, and noise.
         | 
         | That's doable but the double whammy is that most people use the
         | network for 'internet' and 1G is simply more than enough, 10G
         | therefore becomes quite niche so there's no enormous volume to
         | overcome the inherent issues at low cost.
        
         | wmf wrote:
         | 10Gbase-T requires a lot of transistors and power (maybe over
         | 10x more than 1G) so it just wasn't worth the cost.
        
         | AdrianB1 wrote:
         | Ethernet did not stagnate. Ethernet on UTP did stagnate due to
         | reaching the limits of the technology, but Ethernet continues
         | to advance over fiber.
         | 
         | For 10 Gbps I find it simpler and cheaper to use fiber or DACs,
         | but motherboards don't provide SFP+, only RJ45 ports. Over 10
         | Gbps copper is a no go. SFP28 and above would be nice to have
         | on motherboards, but that's a dream with almost zero chances to
         | happen. For most people RJ45 + WiFi 7 is good enough, computer
         | manufacturers will not put SFP+ or SFP28 for a small minority
         | of people.
        
       | cyberax wrote:
       | Ha. I got one of the 10G Thunderbolt adapters a several years
       | ago. And eventually started having problems with Zoom calls
       | around noon. With dropped connections and stuttering. Zoom
       | restarts usually fixed the problem.
       | 
       | After it happened 3-4 times, I started debugging. It turned out
       | that we usually get at least a bit of sunlight around noon, as it
       | burns away the morning clouds. And my Thunderbolt box was in
       | direct sunlight, and eventually started overheating.
       | 
       | And a Zoom restart made it fall back onto the Wifi connection
       | instead of wired.
       | 
       | I fixed that by adding a small USB-powered fan to the Thunderbolt
       | box as a temporary workaround. I just realized that it's been
       | like this for the last 3 years: https://pics.ealex.net/s/overheat
        
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