For secure serial data transmission, the Secure Device Server SN3401 is an external IP-based network device that safely connects older serial RS-232/422/485 devices to an Ethernet network and enables remote access from any computer. The SN3401 is particularly suitable for industrial process control applications, as Supervisory Control and Data Acquisition (SCADA) systems for collecting data from PLCs, measuring instruments, and sensors via serial interfaces are widely used in many industries. The SN3401 translates data bidirectionally between serial and Ethernet formats, allowing access to the data from all data acquisition devices from local and remote locations over an Ethernet network. The SN3401 features a range of useful operating modes. It supports secure TCP server/client, secure serial tunneling server/client, secure Real-COM, and console management modes for security-critical applications such as telecommunications, access control, and remote site management.