Test design for computer network protocols

Communication protocol testing can be done with a test architecture consisting of remote Tester and local Responder processes. By ignoring interaction primitive parameters and additional state variables, it is possible to adapt test sequence generation techniques for finite state machines (FSM) to generate sequences for protocols specified as incomplete finite state machines.For real protocols, tests can be designed based on the formal specification of the protocol which uses an extended FSM model in specifying the transition types. The transition types are transformed into a simpler form called normal form transitions which can be modelled by a control and a data flow graph. Furthermore, the data flow graph is partitioned to obtain disjoint blocks representing the different functions of the protocol. Tests are designed by considering parameter variations of the input primitives of each data flow function and determining the expected outputs. This methodology gives complete test coverage of all data flow functions and tests for unspecified cases can be designed using the control and data flow graphs. The methodology is applied to two real protocols: Transport protocols Classes 0 and 2