Hi Dean,
Not sure if I have understood what exactly you are looking for but here is my reply for this:
Layer 1 is the physical layer - that is, cabling, connectors, etc. The closest thing to a Layer 1 switch would be something like an electrical switch that turns on/off the physical connection between devices, cabling, etc.
Layer 2 switches route traffic based on the Ethernet MAC address. I recommend googling for "OSI model" to learn more about how Ethernet work
The SFP can be added or removed without affecting operations, thus allowing for customization and future upgrades.
HTH
Regards
Inayath
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