WinSURE: a new Windows interface to the SURE program

WinSURE is new interface to the Semi-Markov Range Evaluator (SURE) program, a reliability analysis program used for calculating upper and lower bounds on the operational and death state probabilities for a large class of semi-Markov models. The SURE program was developed in the late 1980s for the Unix environment and has been distributed free-of-charge for over a decade. The WinSURE program is a port of the SURE program to the Windows 98 operating system, providing the same functionality as the original program, but with a Windows-based graphical user interface. The program provides a rapid computational capability for semi-Markov models useful in describing the fault-handling behavior of fault-tolerant computer systems. The only modeling restriction imposed by the program is that the nonexponential recovery transitions must be fast in comparison to the mission time-a desirable attribute of all fault-tolerant reconfigurable systems. The WinSURE reliability analysis method utilizes a fast bounding theorem based on means and variances that enables the calculation of upper and lower bounds on system reliability. This paper presents an overview of the functionality of the WinSURE program, describe the graphical user interface, and illustrate the use of the program on some simple example problems.