Handshaking refers to the process by which two devices, typically modems, lay the groundwork to establish communications between them. Hardware handshaking uses voltage levels or pulses on the wires that connect the devices. Software handshaking uses data units, such as ASCII characters.

The process begins when one of the devices sends a message to another device indicating that it wants to establish a communication channel, or path. The channel is a set of properties that distinguishes one channel from another. In order for the two computers to communicate, the communications properties must be synchronized. The coordination occurs as several more messages are sent back and forth to agree on a communications protocol. Establishing a communications protocol helps ensure that data is transmitted with fidelity.

The handshaking process typically involves the exchange of messages of packets of data. The messages can be of several types. An RTS Enable--request to...