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At least 73 records · Page 4

The Core Flight System (cFS): NASA Quality Flight Software to Power Science and Exploration Available to the World

The presentation is planned to be a continuation of two previous discussions completed at the FSW Workshop regarding the cFS Test Framework (CTF) and Engineering Data Sheets (EDS). The presentation will also cover the latest advancements in cFS, including: 1. Quick into to cFS 2. An overview of our software release process + Git repo 3. Release of EDS files for the cFE + open-source apps 4. Overview of how to independently verify EDS files using CTF + what they can be used for. 5. Future plans for cFS. This presentation complements the talk on configuration management of distributed cFS repos, to be presented by Tam Ngo from Johnson Space Center.

Dan Knutsen↗

Quality and security - They work together

This paper describes the importance of considering computer security as part of software quality assurance practice. The intended audience is primarily those professionals involved in the design, development, and quality assurance of software. Many issues are raised which point to the need ultimately for integration of quality assurance and computer security disciplines. To address some of the issues raised, the NASA Automated Information Security program is presented as a model which may be used for improving interactions between the quality assurance and computer security community of professionals.

Carr, Richard↗

A Reference Model for Software and System Inspections. White Paper

Software Quality Assurance (SQA) is an important component of the software development process. SQA processes provide assurance that the software products and processes in the project life cycle conform to their specified requirements by planning, enacting, and performing a set of activities to provide adequate confidence that quality is being built into the software. Typical techniques include: (1) Testing (2) Simulation (3) Model checking (4) Symbolic execution (5) Management reviews (6) Technical reviews (7) Inspections (8) Walk-throughs (9) Audits (10) Analysis (complexity analysis, control flow analysis, algorithmic analysis) (11) Formal method Our work over the last few years has resulted in substantial knowledge about SQA techniques, especially the areas of technical reviews and inspections. But can we apply the same QA techniques to the system development process? If yes, what kind of tailoring do we need before applying them in the system engineering context? If not, what types of QA techniques are actually used at system level? And, is there any room for improvement.) After a brief examination of the system engineering literature (especially focused on NASA and DoD guidance) we found that: (1) System and software development process interact with each other at different phases through development life cycle (2) Reviews are emphasized in both system and software development. (Figl.3). For some reviews (e.g. SRR, PDR, CDR), there are both system versions and software versions. (3) Analysis techniques are emphasized (e.g. Fault Tree Analysis, Preliminary Hazard Analysis) and some details are given about how to apply them. (4) Reviews are expected to use the outputs of the analysis techniques. In other words, these particular analyses are usually conducted in preparation for (before) reviews. The goal of our work is to explore the interaction between the Quality Assurance (QA) techniques at the system level and the software level.

He, Lulu↗

The NASA Software Research Infusion Initiative: Successful Technology Transfer for Software Assurance

New processes, methods and tools are constantly appearing in the field of software engineering. Many of these augur great potential in improving software development processes, resulting in higher quality software with greater levels of assurance. However, there are a number of obstacles that impede their infusion into software development practices. These are the recurring obstacles common to many forms of research. Practitioners cannot readily identify the emerging techniques that may most benefit them, and cannot afford to risk time and effort in evaluating and experimenting with them while there is still uncertainty about whether they will have payoff in this particular context. Similarly, researchers cannot readily identify those practitioners whose problems would be amenable to their techniques and lack the feedback from practical applications necessary to help them to evolve their techniques to make them more likely to be successful. This paper describes an ongoing effort conducted by a software engineering research infusion team, and the NASA Research Infusion Initiative, established by NASA s Software Engineering Initiative, to overcome these obstacles.

Hinchey, Michael G.↗

Experience with Formal Methods techniques at the Jet Propulsion Laboratory from a quality assurance perspective

Recent experience with Formal Methods (FM) in the Software Quality Assurance Section at the Jet Propulsion Lab is presented. An integrated Formal Method process is presented to show how related existing requirements analysis and FM techniques complement one another. Example application of FM techniques such as formal specifications and specification animators are presented. The authors suggest that the quality assurance organization is a natural home for the Formal Methods specialist, whose expertise can then be used to best advantage across a range of projects.

Kelly, John C.↗

Towards a mature measurement environment: Creating a software engineering research environment

Software engineering researchers are building tools, defining methods, and models; however, there are problems with the nature and style of the research. The research is typically bottom-up, done in isolation so the pieces cannot be easily logically or physically integrated. A great deal of the research is essentially the packaging of a particular piece of technology with little indication of how the work would be integrated with other prices of research. The research is not aimed at solving the real problems of software engineering, i.e., the development and maintenance of quality systems in a productive manner. The research results are not evaluated or analyzed via experimentation or refined and tailored to the application environment. Thus, it cannot be easily transferred into practice. Because of these limitations we have not been able to understand the components of the discipline as a coherent whole and the relationships between various models of the process and product. What is needed is a top down experimental, evolutionary framework in which research can be focused, logically and physically integrated to produce quality software productively, and evaluated and tailored to the application environment. This implies the need for experimentation, which in turn implies the need for a laboratory that is associated with the artifact we are studying. This laboratory can only exist in an environment where software is being built, i.e., as part of a real software development and maintenance organization. Thus, we propose that Software Engineering Laboratory (SEL) type activities exist in all organizations to support software engineering research. We describe the SEL from a researcher's point of view, and discuss the corporate and government benefits of the SEL. The discussion focuses on the benefits to the research community.

Basili, Victor R.↗

Optimizing IV and V for Mature Organizations

NASA is intending for its future software development agencies to have at least a Level 3 rating in the Carnegie Mellon University Capability Maturity Model (CMM). The CMM has built-in Verification and Validation (V&V) processes that support higher software quality. Independent Verification and Validation (IV&V) of software developed by mature agencies can be therefore more effective than for software developed by less mature organizations. How is Independent V&V different with respect to the maturity of an organization? Knowing a priori the maturity of an organization's processes, how can IV&V planners better identify areas of need choose IV&V activities, etc? The objective of this research is to provide a complementary set of guidelines and criteria to assist the planning of IV&V activities on a project using a priori knowledge of the measurable levels of maturity of the organization developing the software.

Fuhman, Christopher↗

A proven approach for more effective software development and maintenance

Modern space flight mission operations and associated ground data systems are increasingly dependent upon reliable, quality software. Critical functions such as command load preparation, health and status monitoring, communications link scheduling and conflict resolution, and transparent gateway protocol conversion are routinely performed by software. Given budget constraints and the ever increasing capabilities of processor technology, the next generation of control centers and data systems will be even more dependent upon software across all aspects of performance. A key challenge now is to implement improved engineering, management, and assurance processes for the development and maintenance of that software; processes that cost less, yield higher quality products, and that self-correct for continual improvement evolution. The NASA Goddard Space Flight Center has a unique experience base that can be readily tapped to help solve the software challenge. Over the past eighteen years, the Software Engineering Laboratory within the code 500 Flight Dynamics Division has evolved a software development and maintenance methodology that accommodates the unique characteristics of an organization while optimizing and continually improving the organization's software capabilities. This methodology relies upon measurement, analysis, and feedback much analogous to that of control loop systems. It is an approach with a time-tested track record proven through repeated applications across a broad range of operational software development and maintenance projects. This paper describes the software improvement methodology employed by the Software Engineering Laboratory, and how it has been exploited within the Flight Dynamics Division with GSFC Code 500. Examples of specific improvement in the software itself and its processes are presented to illustrate the effectiveness of the methodology. Finally, the initial findings are given when this methodology was applied across the mission operations and ground data systems software domains throughout Code 500.

Pajerski, Rose↗

Software engineering and Ada in design

Modern software engineering promises significant reductions in software costs and improvements in software quality. The Ada language is the focus for these software methodology and tool improvements. The IBM FSD approach, including the software engineering practices that guide the systematic design and development of software products and the management of the software process are examined. The revised Ada design language adaptation is revealed. This four level design methodology is detailed including the purpose of each level, the management strategy that integrates the software design activity with the program milestones, and the technical strategy that maps the Ada constructs to each level of design. A complete description of each design level is provided along with specific design language recording guidelines for each level. Finally, some testimony is offered on education, tools, architecture, and metrics resulting from project use of the four level Ada design language adaptation.

Oneill, Don↗

Reliability measurement for operational avionics software

Quantitative measures of reliability for operational software in embedded avionics computer systems are presented. Analysis is carried out on data collected during flight testing and from both static and dynamic simulation testing. Failure rate is found to be a useful statistic for estimating software quality and recognizing reliability trends during the operational phase of software development.

Thacker, J.↗

The quality assurance role in the Deep Space Network

The quality assurance section provides skilled personnel who perform the following functions: quality hardware engineering, quality software engineering, inspection and testing, and an independent assessment to quality, engineering and project requirements. The quality assurance section provides specifications, workmanship standards, process specifications and quality assurance procedures in support of DSN equipment. In addition, the quality assurance section reviews DSN engineering documents to ensure that appropriate and adequate quality provisions are included.

Sirpilla, R. L.↗

Software Engineering Guidebook

The Software Engineering Guidebook describes SEPG (Software Engineering Process Group) supported processes and techniques for engineering quality software in NASA environments. Three process models are supported: structured, object-oriented, and evolutionary rapid-prototyping. The guidebook covers software life-cycles, engineering, assurance, and configuration management. The guidebook is written for managers and engineers who manage, develop, enhance, and/or maintain software under the Computer Software Services Contract.

Connell, John↗

A Probabilistic Software System Attribute Acceptance Paradigm for COTS Software Evaluation

Standard software requirement formats are written from top-down perspectives only, that is, from an ideal notion of a client s needs. Despite the exactness of the standard format, software and system errors in designed systems have abounded. Bad and inadequate requirements have resulted in cost overruns, schedule slips and lost profitability. Commercial off-the-shelf (COTS) software components are even more troublesome than designed systems because they are often provided as is and subsequently delivered with unsubstantiated validation of described capabilities. For COTS software, there needs to be a way to express the client s software needs in a consistent and formal manner using software system attributes derived from software quality standards. Additionally, the format needs to be amenable to software evaluation processes that integrate observable evidence garnered from historical data. This paper presents a paradigm that effectively bridges the gap between what a client desires (top-down) and what has been demonstrated (bottom-up) for COTS software evaluation. The paradigm addresses the specification of needs before the software evaluation is performed and can be used to increase the shared understanding between clients and software evaluators about what is required and what is technically possible.

Morris, A. Terry↗

Shuttle avionics software trials, tribulations and success

The early problems and the solutions developed to provide the required quality software needed to support the space shuttle engine development program are described. The decision to use a programmable digital control system on the space shuttle engine was primarily based upon the need for a flexible control system capable of supporting the total engine mission on a large complex pump fed engine. The mission definition included all control phases from ground checkout through post shutdown propellant dumping. The flexibility of the controller through reprogrammable software allowed the system to respond to the technical challenges and innovation required to develop both the engine and controller hardware. This same flexibility, however, placed a severe strain on the capability of the software development and verification organization. The overall development program required that the software facility accommodate significant growth in both the software requirements and the number of software packages delivered. This challenge was met by reorganization and evolution in the process of developing and verifying software.

Henderson, O. L.↗

Archetyping: A software generation and management methodology

Many knowledge based software generation methods have been proposed to improve software quality and programmer productivity. Several government and industry initiatives have focused on software reusability as one solution to these problems. DARTS (trademark), a General Dynamics proprietary symbolic processing technology, provides a unique solution to the reuse problem: archtyping. Archtyping is the embedding of high order language statements in text files. An advanced macroprocessor uses the text files to generate new versions of complex software systems. A DARTS program, the Software Generation and Configuration Management (SGCM) System automates the archtyping process and maintenance cycle. The DARTS technology is briefly discussed, archtyping is described, and the SGCM system is presented in detail.

Rothman, Hugh B.↗