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by j0057 2508 days ago
In my mind, a "layer 2 subnet" really doesn't mean anything. Subnets are things that happen in IP, that is, layer 3, and layer 2 is the physical connection, ie. Ethernet or WLAN, which don't have the concept of subnets.

Edit: also the OSI layer model was specified in the eighties, and isn't all that accurate in 2019 to describe how our networks actually work.
1 comments
KaiserPro 2508 days ago
I'd argue that the closest thing to a layer 2 subnet is a VLAN.
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stargrazer 2507 days ago
But there isn't a one to one relationship.

A subnet should only be in one vlan, but there are networks where there is more than one subnet in a vlan.

Whether that is appropriate or not, that would be a different topic.

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KaiserPro 2507 days ago
Yes, but that's layer 3 +.

A VLAN will isolate macs so that only those adaptors in that VLAN can see each other. Granted, there isn't really a concept of a netmask based subnet, but then that's because you don't really have control over one's physical address.

Now, you can have an adaptor in more than one VLAN, which is the point of them. As I said its not a perfect analogy, but then they are there to achieve different things based on different semantics.

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