When multiple stations are working together, what must the intermediate stations do?

The correct response highlights the importance of handshaking in communication between multiple stations in a network. Handshaking refers to the process where two devices establish a connection and agree on parameters for communication before data transfer occurs. In an environment with multiple stations, intermediate stations functioning as relays or controllers must engage in handshake protocols with both upstream and downstream stations to ensure that data is transmitted accurately and efficiently throughout the network.

This engagement allows for synchronization, error checking, and flow control, helping to maintain data integrity as it moves through the system. The handshake process is crucial for coordination, particularly when dealing with complex networks where multiple data streams intersect. By acknowledging both upstream and downstream connections, these intermediate stations can effectively manage data flow and address any potential issues that may arise during data exchange.

The other options do not capture the essential function needed for coordination in a multi-station working environment. Establishing separate communications with each station may lead to inefficiencies and increased complexity. Monitoring traffic flow is important but does not directly support the necessary communication protocol between stations. Controlling all connections suggests a centralized oversight which may not always be practical in distributed systems where intermediate stations serve as facilitators rather than controllers. Thus, handshake communication is key for coordinating efforts among multiple stations.