> Typical copper ethernet is 1Gb/s, while USB 3 is 5 Gb/s, going on 10/20/40 Gb/s with USB 3.2, USB 4 .. thunderbolt.
All the bit rates you listed Ethernet also covers. And as for copper - at the speeds you listed thunderbolt and USB3/C are limited to severely short cables, a measly 0.5 meters for 40Gb. Though 20Gb can do 1 or 2m, 2m being the longest thunderbolt cable you can use.
As for power, that devil is in the interface details. I see no reason why multi-gigabit Ethernet can't be pushed over a similarly designed low power differential copper serial transceiver.
As far as I'm concerned, Ethernet is more mature than USB could ever dream of being.
I don't know, but you get the extra limitation of USB2 being half duplex. USB2 is something like 480mbps. Add half duplex limitations and just general overhead compared to theoretical max. I can see how some network protocols become limited to 60mbps.
It's not like we already had a cable and protocol that could encapsulate arbitrary data and transmit it between devices without concern for what upper level protocols were in use or what the data type was, with the only concern with regards to the cable being the max speed supported.
Oh, wait, Ethernet is a thing. I wonder how they just completely missed that when making USB 3. The only thing that should be differentiated between cables is max power delivery rating and data rate.
The problem with pi is USB2.0 with 100M NIC located on USB hub. It's a bottleneck for filesharing throughput. So far there's been no good device that offers USB 3.0 with gigabit ethernet. Even the Pogoplug doesn't count because it has bottlenecks elsewhere.
Reminds me of how excited I was to get a USB Ethernet port for my Packard Bell 1st gen pentium 60mhz that was discounted because it had the floating point bug. But yeah it just didn't work due to failing drivers and that is when I realized that the future promised by these plug and play protocols was going to be fraught by the same hardware compatibility challenges that make building systems hard. I also have a motherboard currently where the usb-c port only works at USB 2.0 speeds in both Linux and Windows. I get the feeling that it is probably just broken for everyone who had this model and support didn't have much to say either. This stuff is hard and one can hope that it eventually gets figured out but I suspect not.
High speed USB 2.0 support is quite rare on cheap chips. Most are still at USB 1.1 speeds.
USB 3 connectors? WAY COOL. I'm running USB 1.1 on the inner pairs and Ethernet on the USB 3 pairs for several projects.
USB 3 standard? Oh, hell, no. The signal integrity requirements are outrageous. And most embedded chips can't even transmit at the 400+Mbps necessary to saturate even USB 2.0.
Looks like the ethernet is connected directly through RGMII - meaning the USB 3.0 controller is likely completely out of the picture. That would mean you can run full throttle ethernet without affecting the USB speed at all.
> if you have a USB 3 hub plugged into a USB 3 port, multiple USB 2 devices plugged into it still cannot break through the USB 2 uplink limit of 480 MBps.
I had a weird project where I ran into this. Or rather, I was actually aware of it and tried to work around it. I wanted to attach a large number of optical drives with sata to USB converters to a single port, basically a hot attachable ripping tower kind of thing. To assure a single port would provide enough bandwidth I needed USB 3.0 throughout. But SATA to USB 3.0 converters that exist seem to have...shaky support for optical drives as they're only really meant for SSDs/HDDs. My project ended in at least temporarily failure due to that unreliability.
I remember reading about this device and not finding it a reasonable solution. In addition to not being easily available, I'd need one device per port to break the uplink limit. That wouldn't save me any money and it would be a cabling nightmare. If the chips were a reasonable price and easily available I might have looked into it more seriously anyway though.
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