When multiple people need to communicate there are various systems that we have produced
Roll call. Goes around to each person and they get to say their piece.
Natural small group conversation. If no body is talking then to ahead and talk. If two people try to talk at same time then stop and wait for an opening.
In networking there are two primary systems used. Token ring doesn't exist much anymore. Ethernet is the predominate networking technique
Token ring is like roll call there is a token that goes around In a circle and only when a consumer has the token may they use the shared resource.
Ethernet or CDMACD is like natural conversation. Listen if nobody is talking then talk. If two talk at same time, both stop talking and try again at a random interval.
Like natural conversation, to many people talking in close proximity and u get a buzz. Also unlike it's natural analogy. Everyone talks in the same tone and speed. Making it impossible to identify separate conversations.
Multiplexing. When u need more than one consumer using a single resource.
Manual switch, switch to the consumer who can use it.
Time based, each consumer gets 5 seconds. And others
AM modulate based on amplitude FM modulate based on frequency
Radio Fiber (Single-Mode, Multi-Mode) Shielded Twisted Pair Coaxial
MAC address CDMACD frequency modulation over a send pair and receive pair of wires.