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Nice project and good work. The only thing is it doesn't address a new or existing market as-is because it competes with what already exists. For example, a Tr

Nice project and good work. The only thing is it doesn't address a new or existing market as-is because it competes with what already exists. For example, a TrendNet 10/100 compact switch (not a hub) goes for $7.31 including shipping on eBay and it comes with a case and a power supply. Decommodifying a product requires finding niches where there is demand like automotive, aerospace, military, or marine applications. Until roughly 2020, 2.88 MB 3.5" floppy drives were in-use primarily in industrial and turnkey commercial systems long after they disappeared from desktop computers. Dinosaur technologies can live on for a very long time, often in critical systems deemed too expensive to replace. Keep pushing forward, learning, and getting better. Btw, if someone made a: - 48 port 10GBASE-T (802.3an-2006) POE++ (IEEE 802.3bt-2018) 960W-1600W+ (3422W would be the upper limit for type 4) - L2 (at least) switch - unmanaged to fully-managed (but no cloud features) - 4 100GBASE QSFP28 uplinks (unpopulated) - dual, hot-swappable PSUs - 2 models: Ports facing either forward or reverse - 19" 1U half rack depth, and wall mountable - Most importantly: doesn't sound like a jet engine under full load by leveraging better engineering, such as using some industrial-rated parts, heatpipes, and moving hotter air but less volume I'd throw down in the $6K price-point neighborhood. Comparables: $4800 FS S5860-48XMG-U is close but sounds like a jet engine with dual 1U screaming PSUs and 3 hot swap chassis fans, but only available in conventional top-of-rack forward facing, leading to longer, messier wire management unnecessarily.

userbinator 2y ago
For example, a TrendNet 10/100 compact switch (not a hub) goes for $7.31 including shipping on eBay and it comes with a case and a power supply A 1G switch from Ali with a case, power supply, and the RJ45 connectors is also under $10.
numpad0 2y ago
This isn't a desktop Ethernet switch. Lots of robotic parts like industrial cameras and fancy laser sensors use Ethernet for interfacing instead of USB or RS232C. Doing so solves cable length limitations and connection stability issues of those peripheral buses. There would be penalties and overheads of (mis?)using inter-node communication protocols like Ethernet (and TCP/IP), but those tradeoffs are completely acceptable. What is not acceptable is full sized switches inside of a robot: they're way too bulky. You may be looking into installing a switch inside a humanoid upper arm or inside pelvis. Regular switches and hubs don't fit there. This product solves that specific robotics packaging problem. Electrically it's a switch/hub, physically it's much smaller than that, that's the point.
- globular-toast 2y ago
  I wonder if you could do away with the switch and just daisy chain in many of those applications. It seems to be forgotten that ethernet supports this.
  - varjag 2y ago
    It's not exactly forgotten. There's 2 wire Ethernet/PoE standard (used mostly in automotive) that can be daisy-chained. Designing for it however is non-trivial and few third party devices (again outside automotive market) support it.
    - globular-toast 2y ago
      Hmm... I thought everything still had collision detection and would work on a bus, like what you'd get using a hub.
      - varjag 2y ago
        There is normally no collision detection beyond 10Mbps. Also PoE would not trivially work daisy chained.
        toast0 2y ago
        100base-Tx is specified for shared media (hub rather than switch), but I think you need some electronics to make a hub, you can't just do a passive connection, and so you probably end up with a hub IC and may as well use a switch IC instead.
      - sgtnoodle 2y ago
        It might work in so far as you'll get packets through. The performance would be abysmal, though. Modern Ethernet is built around switching.
        globular-toast 2y ago
gertrunde 2y ago
I suspect the combination of being able to dissipate 3.4kW of power, and the requested size and noise constraints may put this combination of features firmly beyond reasonable, even before considering cost. But there is always room to hope. :)
- crote 2y ago
  A PoE-supplying switch doesn't need to dissipate that power. Assuming a power supply efficiency of 85%, supplying 3400W to downstream devices means having to dissipate 600W of heat. Keep in mind that you'd be supplying 71W to every single downstream port. That's an insane amount of power. Something like a Cisco Catalyst 9136I Access Point only comes up to 47W, and that's assuming 16 radios, double 5Gbit uplinks, and a USB device drawing 9W.
mike_d 2y ago
A Juniper EX4100 ticks all your boxes. Adding a sound requirement is stupid and ridiculous. You're wanting to take the power supplies from 48 90W devices and put them all in one dense little box and then complaining that it needs to be cool. If you have room for 48 PoE devices, you have room for a properly cooled and sound isoloated IDF.

userbinator 2y ago

For example, a TrendNet 10/100 compact switch (not a hub) goes for $7.31 including shipping on eBay and it comes with a case and a power supply A 1G switch from Ali with a case, power supply, and the RJ45 connectors is also under $10.

numpad0 2y ago

This isn't a desktop Ethernet switch. Lots of robotic parts like industrial cameras and fancy laser sensors use Ethernet for interfacing instead of USB or RS232C. Doing so solves cable length limitations and connection stability issues of those peripheral buses. There would be penalties and overheads of (mis?)using inter-node communication protocols like Ethernet (and TCP/IP), but those tradeoffs are completely acceptable. What is not acceptable is full sized switches inside of a robot: they're way too bulky. You may be looking into installing a switch inside a humanoid upper arm or inside pelvis. Regular switches and hubs don't fit there. This product solves that specific robotics packaging problem. Electrically it's a switch/hub, physically it's much smaller than that, that's the point.

globular-toast 2y ago
I wonder if you could do away with the switch and just daisy chain in many of those applications. It seems to be forgotten that ethernet supports this.
- varjag 2y ago
  It's not exactly forgotten. There's 2 wire Ethernet/PoE standard (used mostly in automotive) that can be daisy-chained. Designing for it however is non-trivial and few third party devices (again outside automotive market) support it.
  - globular-toast 2y ago
    Hmm... I thought everything still had collision detection and would work on a bus, like what you'd get using a hub.
    - varjag 2y ago
      There is normally no collision detection beyond 10Mbps. Also PoE would not trivially work daisy chained.
      - toast0 2y ago
        100base-Tx is specified for shared media (hub rather than switch), but I think you need some electronics to make a hub, you can't just do a passive connection, and so you probably end up with a hub IC and may as well use a switch IC instead.
    - sgtnoodle 2y ago
      It might work in so far as you'll get packets through. The performance would be abysmal, though. Modern Ethernet is built around switching.
      - globular-toast 2y ago

gertrunde 2y ago

I suspect the combination of being able to dissipate 3.4kW of power, and the requested size and noise constraints may put this combination of features firmly beyond reasonable, even before considering cost. But there is always room to hope. :)

crote 2y ago
A PoE-supplying switch doesn't need to dissipate that power. Assuming a power supply efficiency of 85%, supplying 3400W to downstream devices means having to dissipate 600W of heat. Keep in mind that you'd be supplying 71W to every single downstream port. That's an insane amount of power. Something like a Cisco Catalyst 9136I Access Point only comes up to 47W, and that's assuming 16 radios, double 5Gbit uplinks, and a USB device drawing 9W.

mike_d 2y ago

A Juniper EX4100 ticks all your boxes. Adding a sound requirement is stupid and ridiculous. You're wanting to take the power supplies from 48 90W devices and put them all in one dense little box and then complaining that it needs to be cool. If you have room for 48 PoE devices, you have room for a properly cooled and sound isoloated IDF.