Recovery of CFSM-based protocol and service design from protocol executiontraces

Reverse engineering and design recovery are two important concepts for the evolutionary design of systems software. In particular, the reverse enginee ring of distributed software, such as communications software, is a very ch allenging practical problem. Most communications software is written withou t the use of formal methods and is often poorly documented. Consequently, t o maintain or modify such software, relevant details of the original design need to be recovered from the executable software itself. This design reco very process involves either static analysis of the code or dynamic analysi s of the software behaviour based on selected execution traces. In this pap er, we use the dynamic trace analysis approach. Specifically, based on exec ution traces as represented at selected points of observation, we generate a higher level design representation consisting of communicating finite sta te machines (CFSMs) corresponding to the protocol design and service constr aints. Further, the temporal and concurrent aspects of the protocol behavio ur are also captured in the traces and are reflected in the recovered desig n. (C) 1999 Elsevier Science B.V. All rights reserved.