Implementing IEC 60870-5 data link layer for an open and flexible remote unit

This paper presents an open source implementation for a data-link layer protocol specified in IEC 60870, protocol specification for telecontrol networks. It has been tested over LEON an embedded system with a Linux based operating system. Protocol engineering methods have been used in order to implement the protocol. The standard is in natural language so a formal language is needed to describe its behavior. A prototype has also been created to simulate the protocol behavior. The protocol has been tested on a real environment, using PCs and LEON as primary and secondary stations, and different physical layers, serial cable, radio frequency and GSM.