What is the difference between point-to-point subinterfaces and multi-point subinterfaces?

Point-to-point interfaces are used in serial communication. These types of connections are assumed to transmit solely to the station at the opposite end. The examples of Point-to-point are EIA/TIA 232, EIA/TIA 449, X.25, Frame Relay, T-carrier, and OC3 – OC192.

Point-to-multipoint connects one station to several other stations. Point-to-multipoint are of two types

Point-to-multipoint Non-Broadcast

Point-to-multipoint Broadcast

In Point-to-multipoint Non-broadcast, the communication is replicated to all the remote stations. Only specific, selected stations hear the replicated communication. The examples are Frame Relay and ATM.

Point-to-multipoint Broadcast are characterized by a physical medum that connects to all machines and where all communication is heard by all stations.