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> A 1GbE switch with 8 ports needs to be built with 8Gb throughput It needs 16 Gb switching capacity; it is duplex. > What home users need is a 10GbE hub. 10G

> A 1GbE switch with 8 ports needs to be built with 8Gb throughput It needs 16 Gb switching capacity; it is duplex. > What home users need is a 10GbE hub. 10GbE connections between devices but really only one at a time. Switches are overbuilt for home user purposes. Not really. While it is true, that most users do not have active multiple devices at the same time, they would pay for this in energy usage. Ethernet, which is what most people would end up with, has pretty high consumption at 10 GbE, to the tune 3-5W per port (times 2, because you need two ends for each cable). It is better to keep them idle when possible; that means switching.

ziml77 4y ago
> It needs 16 Gb switching capacity; it is duplex. I don't think this is the correct terminology. "Switching capacity", as far as I can tell, is the simple addition of the speeds of all the ports. So 16 Gbps switching capacity isn't something it needs, it's something it has simply from the nature of having those 8x 1 GbE full-duplex ports. What we're talking about here that we'd need to not bottleneck, would be called either "non-blocking throughput" or "backplane bandwidth". And even on higher end switches, the switching capacity and backplane bandwidth are usually not equal. I'd be surprised if the same wasn't true for consumer switches (though maybe it is since there's far fewer ports on consumer switches than enterprise switches). (There's also a packets per second metric that determines how much the switch can handle, but I'm assuming that's only going to be a bottleneck if your packet sizes are too low)
- Hikikomori 4y ago
  These days even most consumer switches except maybe the cheapest ones are non blocking. I picked up one many years ago for $30 for example. Most enterprise gear on the switching side is also non blocking, but there are exceptions of course (Cisco sucks).
dragontamer 4y ago
> It is better to keep them idle when possible; that means switching. Perhaps so. Still, how to switch? If the "switch internals" is just a token-ring + ARP table (IE: each port remembers the mac addresses its serving, and token-rings the data around), the switch will have ~10GbE for all-ports, but only a max bandwidth of 10GbE before it starts losing packets. (Ex: Alice <-> Bob <-> Charlie <-> Dave with only 10GbE each link. If Alice talks to Charlie and Bob talks to Dave, then the Bob -> Charlie needs 20GbE, so half the packets will get dropped) This isn't a full switch classic. Maybe a "Hub classic" isn't enough, since that keeps the ports needlessly active as you noted. But I don't think the full 80Gbps bidirectional is needed for an 8-port home-consumer (or even many prosumer) environments. The full 10Gbps switches all get quite hot, probably due to drawing a ton of power. I'm thinking that some simplified architecture is needed to reduce power (by trading off and reducing bandwidth)

ziml77 4y ago

> It needs 16 Gb switching capacity; it is duplex. I don't think this is the correct terminology. "Switching capacity", as far as I can tell, is the simple addition of the speeds of all the ports. So 16 Gbps switching capacity isn't something it needs, it's something it has simply from the nature of having those 8x 1 GbE full-duplex ports. What we're talking about here that we'd need to not bottleneck, would be called either "non-blocking throughput" or "backplane bandwidth". And even on higher end switches, the switching capacity and backplane bandwidth are usually not equal. I'd be surprised if the same wasn't true for consumer switches (though maybe it is since there's far fewer ports on consumer switches than enterprise switches). (There's also a packets per second metric that determines how much the switch can handle, but I'm assuming that's only going to be a bottleneck if your packet sizes are too low)

Hikikomori 4y ago
These days even most consumer switches except maybe the cheapest ones are non blocking. I picked up one many years ago for $30 for example. Most enterprise gear on the switching side is also non blocking, but there are exceptions of course (Cisco sucks).

dragontamer 4y ago

> It is better to keep them idle when possible; that means switching. Perhaps so. Still, how to switch? If the "switch internals" is just a token-ring + ARP table (IE: each port remembers the mac addresses its serving, and token-rings the data around), the switch will have ~10GbE for all-ports, but only a max bandwidth of 10GbE before it starts losing packets. (Ex: Alice <-> Bob <-> Charlie <-> Dave with only 10GbE each link. If Alice talks to Charlie and Bob talks to Dave, then the Bob -> Charlie needs 20GbE, so half the packets will get dropped) This isn't a full switch classic. Maybe a "Hub classic" isn't enough, since that keeps the ports needlessly active as you noted. But I don't think the full 80Gbps bidirectional is needed for an 8-port home-consumer (or even many prosumer) environments. The full 10Gbps switches all get quite hot, probably due to drawing a ton of power. I'm thinking that some simplified architecture is needed to reduce power (by trading off and reducing bandwidth)