Full-duplex protocols allow an application program to send and receive information concurrently. This allows the application sending information to continue without waiting for a response from the partner LU. The partner LU can also send information without waiting for an appropriate response. Neither LU has to wait for the partner LU to surrender its right to receive or send information.

Full-duplex conversations are especially suited for transactions in which the data sent and received is either independent or indirectly related (for example, process control). This is advantageous for transactions in which an immediate response is desired. For example, sensor data (temperature, for example) is continuously received in a process control environment and corrective information is continuously sent. A full-duplex conversation allows the controlling application to detect an abnormal condition and respond to correct the condition immediately. Fewer system resources are used, and the integrity of the environment is maintained.

Because full-duplex conversations are not suited for tightly coupled transactions such as sync point and inquiry-reply transactions, sync point is not supported for full-duplex conversations.