Mono means single
Unilateral means "On,having,or confined to only one side."
Bilateral means "Having or formed of two sides; two-sided."
These are all used as prefixes here.
Communication means the exchange of thoughts,messages,or information,as by speech,signals,writing,or behavior.
So
1.Mono-communication means a single communication
2.Unilateral-communication means a one-sided communication
3.Bilateral-communication means a two-sided communication