A Formal Description Technology: Graphics E-LOTOS

In this paper, we propose a method of Formal Description Technology (FDT) GE-LOTOS---a Graphical mode of Enhanced LOTOS (E-LOTOS). Compared with the existing FDT, the GE-LOTOS presented here has greater formal description capability. But GE-LOTOS only has a limited set of simple graphical patterns. Using the hierarchical structures of GE-LOTOS we can describe the structure and hierarchy of protocol more clearly and directly than using the existing E-LOTOS. Meanwhile the GE_LOTOS has another merit over the existing E_LOTOS that it can be executed easily and the system behavior is conveniently visible, so the system can be easily monitored and modified. We have developed a designing system for creating GE-LOTOS specifications under Java Cafe environment, and with further enhancement this system can be used for protocol testing and verification. The GE-LOTOS can be used as a design, execution, verification and testing tool for network communication protocol.