Assessing the Software Control Autonomy of System Functions in Safety-Critical Systems

Vu Tran; Viet Tran; Long Tran

doi:10.56094/jss.v57i3.206

Authors

Vu N. Tran Naval Air Warfare Center - Weapons Division https://orcid.org/0000-0001-9064-8262
Viet N. Tran University of Southern California https://orcid.org/0000-0002-8078-6925
Long V. Tran United States Air Force https://orcid.org/0000-0003-0343-2768

DOI:

https://doi.org/10.56094/jss.v57i3.206

Keywords:

software safety, software control category, hazard analysis, safety process

Abstract

Software Control Category (SCC) denotes the degree of control autonomy, command and control authority, and redundant fault tolerance software has over hazardous system functions of safety-critical systems. The use of SCC for determining the software contribution to system risks is a unique feature of the MIL-STD-882E System Safety Standard. A lower SCC designation means that the software system has a greater control autonomy over hazardous system functions, whereas SCC 1 means complete autonomous control. Software with greater control autonomy over hazardous system functions require greater effort to assure reliability and safety. Correct assessment of the SCC level of hazardous system functions is crucial for optimizing the safety property of a system developed under budget, schedule, and resource constraints. Beyond the categorical definitions provided by the MIL-STD-882E Standard, there is little information on conducting an SCC assessment. To close this knowledge gap, we present an SCC assessment method. Our paper will describe in detail the process and rules for assessing SCC. For illustration, we apply our method to assess the SCC of several safety-significant functions of an automobile’s brake-assist system.

Author Biographies

Vu N. Tran, Naval Air Warfare Center - Weapons Division

Dr. Vu Tran is a civilian computer scientist at the NAWCWD since 2019. He supports different weapons and unmanned aircraft safety programs from China Lake, CA. Prior to joining NAWCWD, Dr. Tran spent 30 years in the defense and commercial sectors, including the last fifteen years as a technical director overseeing the development and operations of security systems protecting direct-to-home (DTH) satellite and cable businesses in North America, Europe, the Middle East, and Asia. In the U.S., he oversaw the successful secure engineering of the DIRECTV broadcasting system for almost 20 years. Dr. Tran received his doctorate in Organizational Leadership from Pepperdine University, an M.S. in Computer Engineering from Cal State University at Long Beach, an MBA in Business, and a B.S. in Information and Computer Science from the University of California at Irvine. He served as the IT executive committee member of the Organizational Behavior division of the Academy of Management between 2007-2010. He was a part-time faculty member of the School of Business and Technology at Capella University between 2013-2022. Dr. Tran published over two dozen papers in conferences and journals of the IEEE, ACM, and AoM.

Viet N. Tran, University of Southern California

Viet Tran is an undergraduate student at USC in Mechanical Engineering. He has held research internship positions with NASA and the MIT Lincoln Lab.

Long V. Tran, United States Air Force

Long V. Tran is a research assistant at the University of Southern California and a developmental officer with the United States Air Force

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