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by crote 4 days ago
Sure, but at that point you're just building a complicated hub, and trying to actually operate it at speed would result in most packages getting dropped due to collisions as it is pretending to be full-duplex while actually only being half-duplex.
2 comments
zamadatix 3 days ago
What do you mean by "pretending to be full duplex"?
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inigyou 3 days ago
Modern Ethernet networks can be full-duplex because of all the buffering and separation between ports. If you're running ethernet on an actual shared medium like 10BASE5 or hubbed ethernet, it has to be half duplex to handle collisions better.

And the proposed switch design - transmitting most packets to most ports without buffering - is basically a hub. If you transmit two packets at the same time you will most likely create a collision. A real switch can buffer one of the packets.

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zamadatix 1 day ago
What you're describing are drops, which behave differently than collisions. No frame is successfully delivered in a collision while one is during a drop. This project cannot have collisions because the links are full duplex.

Unknown flooding is actually a pretty base requirement of ethernet switches per the 802.1 standard, even when the table is not full, anyways. Without it you can't form switched paths unless every switch in the path has recently heard a broadcast (or following regular flow) from the intended receiver. If you start each test case as a short loved one with an IPv4 client ARPing for neighbors or in a simple topology the this can easily be missed but wreak havoc in the real world. To not do so is as egregious to say you're an ethernet switch which does not flood broadcasts in terms of false claims of being an Ethernet compliant switch.

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inigyou 3 days ago
Ethernet switches are complicated hubs.
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throw0101a 3 days ago
Some of the 'old' names:

> A network switch (also called switching hub, bridging hub, Ethernet switch, and—by the IEEE—MAC bridge[1]) is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destination device.

* https://en.wikipedia.org/wiki/Network_switch

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