ADDER Infinity User Manual page 54

The job of any network switch is to receive each incoming
network packet, strip away only the first few wrappers to
discover the intended destination then rewrap the packet
and send it in the correct direction.
In simplified terms, the wrapper that is added at Layer 2
(by the sending system) includes the physical address of
the intended recipient system, i.e. the unique MAC address
(for example, 09:f8:33:d7:66:12) that is assigned to every
networking device at manufacture. Deciphering recipients
at this level is more straightforward than at Layer 3, where
the address of the recipient is represented by a logical IP
address (e.g. 192.168.0.10) and requires greater knowledge
of the surrounding network structure. Due to their more
complex circuitry, Layer 3 switches are more expensive
than Layer 2 switches of a similar build quality and are
used more sparingly within installations.
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