Data communications are becoming more extensively used in the maritime mobile services. With no current general protocol profile that can be used for data communications between mobile services, it will be advantageous to develop protocols that adhere to the Open System Interconnection (OSI) standards. Implementation of such protocols will allow multiple shipboard equipment to communicate via a shipborne network and then transmit the data to a shore-based network in an effective and efficient manner. Automatic Repeat reQuest (ARQ) techniques are often used by packet-switching networks to provide error-free communication links between network nodes. Information throughput is highly link dependent; as the noise or interference on the link increases, throughput decreases. To improve the throughput on a packet switching communications network, an adaptive ARQ strategy is developed and applied to the Stop-and-Wait protocol. A comparison of the throughput efficiencies of the simulated adaptive SW protocol with the non-adaptive SW protocol showed a marked improvement in throughput when the communication links are subjected to high channel bit error rates. DLC, Adaptive protocol.