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The use of a software toolkit and development methodology that supports software reuse is described. The toolkit includes source-code-level library modules and stand-alone tools which support such tasks as data reformatting and report generation, simple relational database applications, user interfaces, tactical planning, strategic planning and documentation. The current toolkit is written in C and supports applications that run on IBM-PC's under DOS and UNlX-based workstations under OpenLook and Motif. The toolkit is fully integrated for building scheduling systems that reuse AI knowledge base technology. A typical scheduling scenario and three examples of applications that utilize the reuse toolkit will be briefly described. In addition to the tools themselves, a description of the software evolution and reuse methodology that was used is presented.

The use of a software toolkit and development methodology that supports software reuse is described. The toolkit includes source-code-level library modules and stand-alone tools which support such tasks as data reformatting and report generation, simple relational database applications, user interfaces, tactical planning, strategic planning and documentation. The current toolkit is written in C and supports applications that run on IBM-PC's under DOS and UNlX-based workstations under OpenLook and Motif. The toolkit is fully integrated for building scheduling systems that reuse AI knowledge base technology. A typical scheduling scenario and three examples of applications that utilize the reuse toolkit will be briefly described. In addition to the tools themselves, a description of the software evolution and reuse methodology that was used is presented.

The Software Productivity Consortium is sponsored by 14 aerospace companies as a developer of software engineering methods and tools. Software reuse and prototyping are currently the major emphasis areas. The Methodology and Measurement Project in the Software Technology Exploration Division has developed some concepts for reuse which they intend to develop into a synthesis process. They have identified two approaches to software reuse: opportunistic and systematic. The assumptions underlying the systematic approach, phrased as hypotheses, are the following: the redevelopment hypothesis, i.e., software developers solve the same problems repeatedly; the oracle hypothesis, i.e., developers are able to predict variations from one redevelopment to others; and the organizational hypothesis, i.e., software must be organized according to behavior and structure to take advantage of the predictions that the developers make. The conceptual basis for reuse includes: program families, information hiding, abstract interfaces, uses and information hiding hierarchies, and process structure. The primary reusable software characteristics are black-box descriptions, structural descriptions, and composition and decomposition based on program families. Automated support can be provided for systematic reuse, and the Consortium is developing a prototype reuse library and guidebook. The software synthesis process that the Consortium is aiming toward includes modeling, refinement, prototyping, reuse, assessment, and new construction.

The Space Station Freedom Program (SSFP) Level 2 Software Reuse Study group was formed by Bob Nelson (NASA SSFP) from members of the Information Systems Program Support Contract (PSC) team. The objectives of the study were to identify existing software reuse libraries, to identify existing reusability processes and experiences, to identify reusability analysis tools and users, and to provide recommendations for a software reusability process for the SSFP. To date the following have been delivered: (1) definitions of commonality and reuse, (2) a report on existing software reuse libraries and library management systems, (3) a report on reuse process and methodology gleaned from software reuse experts, and (4) a report on software attributes for measuring commonality and reusability. Three implementation alternatives for a repository of reusable components were identified: centralized at the SSE Development Facility (SSEDF), a distributed approach across the network of Software Production Facilities, and a directory approach. A number of findings from the reuse study and several reuse strategy considerations were presented.

This paper reports on the progress of a study which will contribute to our ability to perform high-level, component-based programming by describing means to obtain useful components, methods for the configuration and integration of those components, and an underlying economic model of the costs and benefits associated with this approach to reuse. One goal of the study is to develop and demonstrate methods to recover reusable components from domain-specific software through a combination of tools, to perform the identification, extraction, and re-engineering of components, and domain experts, to direct the applications of those tools. A second goal of the study is to enable the reuse of those components by identifying techniques for configuring and recombining the re-engineered software. This component-recovery or software-cycle model addresses not only the selection and re-engineering of components, but also their recombination into new programs. Once a model of reuse activities has been developed, the quantification of the costs and benefits of various reuse options will enable the development of an adaptable economic model of reuse, which is the principal goal of the overall study. This paper reports on the conception of the software-cycle model and on several supporting techniques of software recovery, measurement, and reuse which will lead to the development of the desired economic model.

Verification and validation (V&V) is used to increase the level of assurance of critical software, particularly that of safety-critical and mission critical software. This paper describes the working group's success in identifying V&V tasks that could be performed in the domain engineering and transition levels of reuse-based software engineering. The primary motivation for V&V at the domain level is to provide assurance that the domain requirements are correct and that the domain artifacts correctly implement the domain requirements. A secondary motivation is the possible elimination of redundant V&V activities at the application level. The group also considered the criteria and motivation for performing V&V in domain engineering.

As space mission design trends towards shared, multi-mission platforms and high-performance onboard computing architectures, the number of spacecraft launched into operation is also steadily rising. Through ridesharing, spacecraft miniaturization, and other cost-reduction measures, the barriers to space are lowering, resulting in compounded growth in the amount of flight software being deployed. To meet the needs of both the growing quantity and evolving nature of spacecraft, flight software design must accordingly adapt to support more efficient development, solutions to computational resource-sharing, and software reusability. This paper focuses on a software payload demonstrating several core technologies that improve the state-of-the-art in these identified areas. Launched into low-earth orbit in January 2022, our software payload was conceived, designed, and delivered in a span of merely two months. It was developed on top of the NASA core Flight System (cFS) framework and the Distributed Spacecraft Autonomy (DSA) Comm cFS application, which translates cFS software bus messages across a Data Distribution Service (DDS) network. The flight software, packaged in Linux container images, was deployed as one of 18 flight applications managed through the Unibap SpaceCloud Framework. The applications were run on a Unibap iX5-102 radiation-tolerant payload computer, hosted on the D-Orbit SCV-004 spacecraft as part of an ESA-sponsored in-orbit technology test.\n\nOur payload, referred to as the DSA D-Orbit software, demonstrates the reusability of the DSA Comm app in a substantially different context and purpose as its original mission. Comm’s original design goal was to reliably distribute messages between spacecraft swarms of arbitrary size and dynamic network topology. However, we leverage this same functionality to introduce redundancy and opportunistic parallel data processing in the context of a representative onboard image processing workload. This adaptive mission architecture was enabled in part by the SpaceCloud Framework’s use of container virtualization as the payload\nintegration interface. By using a base container image with common high-level language runtimes and libraries, we were able to rapidly design, develop, and validate our image processing application without many of the technological barriers common to flight software development. We present details the goals, approach, results, and lessons learned through this technology demonstration experiment and contextualize those observations against present and future challenges in spacecraft software development.

As space mission design trends towards shared, multi-mission platforms and high-performance onboard computing architectures, the number of spacecraft launched into operation is also steadily rising. Through ridesharing, spacecraft miniaturization, and other cost-reduction measures, the barriers to space are lowering, resulting in compounded growth in the amount of flight software being deployed. To meet the needs of both the growing quantity and evolving nature of spacecraft, flight software design must accordingly adapt to support more efficient development, solutions to computational resource-sharing, and software reusability. This paper focuses on a software payload demonstrating several core technologies that improve the state-of-the-art in these identified areas. Launched into low-earth orbit in January 2022, our software payload was conceived, designed, and delivered in a span of merely two months. It was developed on top of the NASA core Flight System (cFS) framework and the Distributed Spacecraft Autonomy (DSA) Comm cFS application, which translates cFS software bus messages across a Data Distribution Service (DDS) network. The flight software, packaged in Linux container images, was deployed as one of 18 flight applications managed through the Unibap SpaceCloud Framework. The applications were run on a Unibap iX5-102 radiation-tolerant payload computer, hosted on the D-Orbit SCV-004 spacecraft as part of an ESA-sponsored in-orbit technology test.\n\nOur payload, referred to as the DSA D-Orbit software, demonstrates the reusability of the DSA Comm app in a substantially different context and purpose as its original mission. Comm’s original design goal was to reliably distribute messages between spacecraft swarms of arbitrary size and dynamic network topology. However, we leverage this same functionality to introduce redundancy and opportunistic parallel data processing in the context of a representative onboard image processing workload. This adaptive mission architecture was enabled in part by the SpaceCloud Framework’s use of container virtualization as the payload\nintegration interface. By using a base container image with common high-level language runtimes and libraries, we were able to rapidly design, develop, and validate our image processing application without many of the technological barriers common to flight software development. We present details the goals, approach, results, and lessons learned through this technology demonstration experiment and contextualize those observations against present and future challenges in spacecraft software development.

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The Goddard Space Flight Center (GSFC) work is organized into four phases and includes participation by a contractor, CTA, Inc. The first phase was an automation study, which began with a comprehensive survey of software development automation technologies. Eight technical areas were analyzed for goals, current capabilities, and obstacles. The study documented current software development practice in GSFC Mission Operations and Data Systems Directorate, and presented short- and long-term recommendations that included focus on reuse and object-oriented development. The second phase, which has been completed, developed a prototype reuse environment with tools supporting object-oriented requirements analysis and design. This phase addressed the operational concept of software reuse, i.e., it attempted to understand how software can be reused. This environment has two semantic networks: object and keywords, and includes automated search, interactive browsing and a graphical display of database contents. Phase 3 was a domain analysis of Payload Operations Control Center (POCC) software. The goal in this phase was to create an initial repository of reusable components and techniques. Seven existing Operations Control Centers at GSFC were studied, but the domain analysis proved to be very slow. A lesson learned from this was that senior people who understand the environment and the functionality of the area are needed to perform successful domain analyses.

The Goddard Space Flight Center (GSFC) work is organized into four phases and includes participation by a contractor, CTA, Inc. The first phase was an automation study, which began with a comprehensive survey of software development automation technologies. Eight technical areas were analyzed for goals, current capabilities, and obstacles. The study documented current software development practice in GSFC Mission Operations and Data Systems Directorate, and presented short- and long-term recommendations that included focus on reuse and object-oriented development. The second phase, which has been completed, developed a prototype reuse environment with tools supporting object-oriented requirements analysis and design. This phase addressed the operational concept of software reuse, i.e., it attempted to understand how software can be reused. This environment has two semantic networks: object and keywords, and includes automated search, interactive browsing and a graphical display of database contents. Phase 3 was a domain analysis of Payload Operations Control Center (POCC) software. The goal in this phase was to create an initial repository of reusable components and techniques. Seven existing Operations Control Centers at GSFC were studied, but the domain analysis proved to be very slow. A lesson learned from this was that senior people who understand the environment and the functionality of the area are needed to perform successful domain analyses.

We analyze software reuse from the perspective of information theory and Kolmogorov complexity, assessing our ability to ``compress'' programs by expressing them in terms of software components reused from libraries. A common theme in the software reuse literature is that if we can only get the right environment in place-- the right tools, the right generalizations, economic incentives, a ``culture of reuse'' -- then reuse of software will soar, with consequent improvements in productivity and software quality. The analysis developed in this paper paints a different picture: the extent to which software reuse can occur is an intrinsic property of a problem domain, and better tools and culture can have only marginal impact on reuse rates if the domain is inherently resistant to reuse. We define an entropy parameter $H \in [0,1]$ of problem domains that measures program diversity, and deduce from this upper bounds on code reuse and the scale of components with which we may work. For ``low entropy'' domains with $H$ near 0, programs are highly similar to one another and the domain is amenable to the Component-Based Software Engineering (CBSE) dream of programming by composing large-scale components. For problem domains with $H$ near 1, programs require substantial quantities of new code, with only a modest proportion of an application comprised of reused, small-scale components. Preliminary empirical results from Unix platforms support some of the predictions of our model.

In August 2006, Program Executive Officer of Integrated Warfare Systems (PEO-IWS), established the Software Hardware Asset Reuse Enterprise (SHARE) repository to enable the reuse of combat system software and related assets. In July 2007, the Naval Postgraduate School (NPS) was tasked to develop a component specification and ontology for the SHARE repository. A description of SHARE and the requirements for a component specification and ontology supporting this repository are available in Johnson (2007). A vision of the component specification and ontology for the repository framework, a brief survey of initiatives and technologies relevant to desired repository capabilities, a development approach, and initial design are described in Johnson & Blais (2008). The current report provides the initial component specification and ontology for the repository framework, as well as initial information models supporting future implementation of stronger semantic representations of assets and artifacts in the repository. The document provides recommendations for improvements to descriptions of information stored in the repository to enable more effective search, discovery, and use of information. The initial component specification and ontology will help meet near-term repository objectives and will set the foundation for achieving long-term resource discovery objectives in the Global Information Grid context.

Much attention has been paid to software reuse in recent years because it is recognized as a key means for obtaining higher productivity in the development of new software systems. Also, software reuse has provided the technical benefit of reduced error content and thus higher quality. The primary economics benefit of software reuse is cost reduction. Reuse of an existent software object generally costs much less than creating a new one. An earlier Consortium technical report (Cruickshank and Gaffney 1990) presented an economics model of the Consortium's Synthesis system for systematic software reuse. This report extends this work. The reuse economics model presented here should be regarded as a tool to aid in the exploration of the economics benefits of software reuse but not as an algorithm that covers all possible cases of reuse. The framework provided will aid the analyst and the project manager in making economics decisions about software reuse. The model covers various topics, including the effect of various strategies of investing in the creation of reusable software objects (RSOs), the cost effects of reusing requirements or design in addition to the costs of reusing code, and the effects of reuse on software quality.

Much attention has been paid to software reuse in recent years because it is recognized as a key means for obtaining higher productivity in the development of new software systems. Also, software reuse has provided the technical benefit of reduced error content and thus higher quality. The primary economics benefit of software reuse is cost reduction. Reuse of an existent software object generally costs much less than creating a new one. An earlier Consortium technical report (Cruickshank and Gaffney 1990) presented an economics model of the Consortium's Synthesis system for systematic software reuse. This report extends this work. The reuse economics model presented here should be regarded as a tool to aid in the exploration of the economics benefits of software reuse but not as an algorithm that covers all possible cases of reuse. The framework provided will aid the analyst and the project manager in making economics decisions about software reuse. The model covers various topics, including the effect of various strategies of investing in the creation of reusable software objects (RSOs), the cost effects of reusing requirements or design in addition to the costs of reusing code, and the effects of reuse on software quality.

Much attention has been paid to software reuse in recent years because it is recognized as a key means for obtaining higher productivity in the development of new software systems. Also, software reuse has provided the technical benefit of reduced error content and thus higher quality. The primary economics benefit of software reuse is cost reduction. Reuse of an existent software object generally costs much less than creating a new one. An earlier Consortium technical report (Cruickshank and Gaffney 1990) presented an economics model of the Consortium's Synthesis system for systematic software reuse. This report extends this work. The reuse economics model presented here should be regarded as a tool to aid in the exploration of the economics benefits of software reuse but not as an algorithm that covers all possible cases of reuse. The framework provided will aid the analyst and the project manager in making economics decisions about software reuse. The model covers various topics, including the effect of various strategies of investing in the creation of reusable software objects (RSOs), the cost effects of reusing requirements or design in addition to the costs of reusing code, and the effects of reuse on software quality.

Software reuse has become a critical issue as public and private entities struggle to control cost in the expensive field of applications development and authors of software products act to protect their intellectual property rights. Software customers who are engaged in end-use development hope to be able to negotiate reuse contracts that allow them to economically develop complete applications. This thesis investigates the history and discusses the legal issues surrounding the reuse of software as intellectual property. It concludes by discussing several measures for dealing with the legal barriers to software reuse.

Software reuse has become a critical issue as public and private entities struggle to control cost in the expensive field of applications development and authors of software products act to protect their intellectual property rights. Software customers who are engaged in end-use development hope to be able to negotiate reuse contracts that allow them to economically develop complete applications. This thesis investigates the history and discusses the legal issues surrounding the reuse of software as intellectual property. It concludes by discussing several measures for dealing with the legal barriers to software reuse.

The current state of the art in software reuse is to provide problem domain components and problem domain objects. It is shown that designing verbatim resuable components at the architecture level can create approximately the same savings as the current state of the art. The new approach that needs to be applied to future systems is to strictly separate the problem domain objects from the particular systems architecture and to build the problem domain layers from bottom-up. When this approach is used to develop verbatim reusable software, the resources saved can be applied to new problems (extending the problem domain) or to provide better solutions to existing problems by upgrading the architecture.

This thesis describes a web-based continuous learning module (CLM) for use in introducing members of the Department of the Navy's acquisition community to software reuse in the context of Naval Open Architecture. The CLM introduces the student to principles for effective software reuse, explains the unique challenges of software reuse, discusses software reuse within the context of the Naval Open Architecture under the current Department of Defense and DoN policy and guidance, provides a strategy for successful software reuse, and introduces the student to the Software Hardware Asset Reuse Enterprise (SHARE) repository established by the Navy's Open Architecture (OA) program.

The goal of this Technology Reinvestment Program Focus Area is to radically reduce the effort required to field new software applications through the development of reusable software components. Today an estimated 85% of the installed base is a custom application, with all components written especially for that software package. Object Oriented Software, an emerging software technology, which is becoming widely used in the development of new software, offers the promise of reusability and ease of modification for both Defense and commercial applications. However, the promise can only be realized if the use of object oriented software is created according to an established set of standards and if appropriate reusable software components are developed. Building on emerging industry standards for software object technologies, these projects will significantly accelerate development of tools to help build the infrastructure for component ware, create a pool of developers experienced with applying the new tools, and deliver a series of demonstration applications with both commercial and defense relevance.

Establishing and operating software repositories are important elements in the DoD's plan to encourage software reuse. One way to manage such repositories is through a fee-for-service arrangement, which involves charging a fee to the users of the repositories and using the proceeds to reimburse the repository for costs incurred in providing products and services. This paper examines the economic foundations for setting prices for repository products and services that strike an optimal balance between encouraging reuse and recovering costs. We argue that the most important issue in pricing is ownership of the assets. We believe that the most likely outcome under government ownership is a repository full of unusable and unused software assets, and maintain that private ownership would create incentives to supply truly reusable assets. In addition, the private ownership scheme eliminates the government's responsibility for dealing with the complicated problems associated with setting the price of repository assets and a few repository services.

The Object-oriented Reuse Tool (ORT) provides support for the reuse of object-oriented software by maintaining a library of reusable classes, recording information about reusability, allowing easy exploration of library entries, and providing an extensible approach to facilitating reuse in a software development environment. ORT takes advantage of opportunities provided by the object-oriented style of programming that are unavailable in reuse schemes for conventional programming languages. It also records information useful in assessing the reusability of library entries and in relating these entries to each other. In the early design phases of object-oriented development, ORT facilitates reuse by providing a flexible way to navigate the classes recorded in library and the information associated with them. It thereby aids in the process of refining a design to maximally reuse existing classes. The implementation of ORT is extensible. A collection of other useful tools have been identified. These tools can be directly implemented within the existing architecture and would compose the remainder of a practical system useful in increasing the amount of reuse in an objected-oriented software development environment. Keywords: Software reuse; Object-oriented software; Libraries; Reusability information; Software development; Querying, Browsing; Computer programs.

Viewgraphs are presented on the designing of software for reuse. Topics include terminology, software reuse maxims, the science of programming, an interface design example, a modularization example, and reuse and implementation guidelines.

Inheritance is a powerful mechanism supported by object-oriented programming languages to facilitate modifications and extensions of reusable software components. This paper presents a taxonomy of the various purposes for which an inheritance mechanism can be used. While some uses of inheritance significantly enhance software reuse, some others are not as useful and in fact, may even be detrimental to reuse. The paper discusses several examples, and argues for a programming language design that is selective in its support for inheritance.

There is a strong operational interest in reuse and commonality at the Johnson Space Center (JSC). Although commonality and reuse were not emphasized in the Space Shuttle Orbiter Project, it is a major goal for Space Station Freedom and the Software Support Environment (SSE). Research activities at JSC are generally conducted through the Software Engineering Research Center (SERC) of the University of Houston at Clear Lake. The Life Cycle Model developed by SERC includes reuse at each phase, but reuse is not a principal theme. The SSE is a significant entry point for new reuse technology, and the SERC can provide consultation and possible prototypes. SERC is seen as an interface to other NISE reuse researchers. The AdaNET is managed at JSC through the University of Houston at Clear Lake for the NASA Office of Technology Utilization. It may also be a gateway for reuse research.

There is a strong operational interest in reuse and commonality at the Johnson Space Center (JSC). Although commonality and reuse were not emphasized in the Space Shuttle Orbiter Project, it is a major goal for Space Station Freedom and the Software Support Environment (SSE). Research activities at JSC are generally conducted through the Software Engineering Research Center (SERC) of the University of Houston at Clear Lake. The Life Cycle Model developed by SERC includes reuse at each phase, but reuse is not a principal theme. The SSE is a significant entry point for new reuse technology, and the SERC can provide consultation and possible prototypes. SERC is seen as an interface to other NISE reuse researchers. The AdaNET is managed at JSC through the University of Houston at Clear Lake for the NASA Office of Technology Utilization. It may also be a gateway for reuse research.

NASA's Space Communication and Navigation Testbed is beginning operations on the International Space Station this year. The objective is to promote new software defined radio technologies and associated software application reuse, enabled by this first flight of NASA's Space Telecommunications Radio System architecture standard. The Space Station payload has three software defined radios onboard that allow for a wide variety of communications applications; however, each radio was only launched with one waveform application. By design the testbed allows new waveform applications to be uploaded and tested by experimenters in and outside of NASA. During the system integration phase of the testbed special waveform test modes and stand-alone test waveforms were used to characterize the SDR platforms for the future experiments. Characterization of the Testbed's JPL SDR using test waveforms and specialized ground test modes is discussed in this paper. One of the test waveforms, a record and playback application, can be utilized in a variety of ways, including new satellite on-orbit checkout as well as independent on-board testbed experiments.

Scientific missions in the Earth sciences frequently require cost-effective, highly reliable, and easy-to-use software, which can be a challenge for software developers to provide. The NASA Earth Science Enterprise (ESE) spends a significant amount of resources developing software components and other software development artifacts that may also be of value if reused in other projects requiring similar functionality. In general, software reuse is often defined as utilizing existing software artifacts. Software reuse can improve productivity and quality while decreasing the cost of software development, as documented by case studies in the literature. Since large software systems are often the results of the integration of many smaller and sometimes reusable components, ensuring reusability of such software components becomes a necessity. Indeed, designing software components with reusability as a requirement can increase the software reuse potential within a community such as the NASA ESE community. The NASA Earth Science Data Systems (ESDS) Software Reuse Working Group is chartered to oversee the development of a process that will maximize the reuse potential of existing software components while recommending strategies for maximizing the reusability potential of yet-to-be-designed components. As part of this work, two surveys of the Earth science community were conducted. The first was performed in 2004 and distributed among government employees and contractors. A follow-up survey was performed in 2005 and distributed among a wider community, to include members of industry and academia. The surveys were designed to collect information on subjects such as the current software reuse practices of Earth science software developers, why they choose to reuse software, and what perceived barriers prevent them from reusing software. In this paper, we compare the results of these surveys, summarize the observed trends, and discuss the findings. The results are very similar, with the second, larger survey confirming the basic results of the first, smaller survey. The results suggest that reuse of ESE software can drive down the cost and time of system development, increase flexibility and responsiveness of these systems to new technologies and requirements, and increase effective and accountable community participation.

Software cost for DoD is a critical issue. Software reuse promises significant cost savings by using previously developed components thus increasing productivity. Quality is improved because these components are well designed, well documented, and well tested. This thesis studies the determinants of software reuse using a system dynamics computer model, the Dynamcia Reuse Model, which simulates the activities of a software development organization engaged in organization-wide, systematic software reuse. Results indicate that setting goals of consumption and production of components too low will lead to a decreased reuse rate of turnover of personnel. In the area of consumption and production costs of reusable components, production costs are more critical. Regarding employee turnover, reuse is enhanced by a low rate of turnover of personnel. In establishing a successful reuse program, creating repository is an important factor and the study indicates there is a structurally stable repository value. Concerning the software development rate of components, a steady development rate leads to a more consistent reuse rate. DoD managers can now us these results in formulating policies concerning their systematic reuse program.

Software continues to be the single greatest challenge facing DoD systems developers. The criticality of software as a integral component of system design, continues to grow in importance as DoD moves into the 21st Century. To meet this ever increasing challenge, software development organizations are incorporating new design requirements and practices into their development processes. These new requirements/practices, properly implemented into the development process, can reduce software development and maintenance costs and increase software quality and development productivity. This thesis investigates the impact of three management-selected software development requirements/practices--CASE tools, Ada, and software reuse--on the progress of a particular DoD software development project, known as Project X. After a brief introduction the thesis presents background literature on the three development requirements of Project X. The background literature is used to support the Project X case study. Information required for the case study is obtained through interviews with Project X affiliated development personnel. Interview results are analyzed and interpreted through a comparison with information found in the background literature. Results of the case study identify several problems with management's plan to implement the three development requirements into Project X. The thesis identifies specific root causes for the implementation problems, and makes recommendations to reduce the impact of these problems on Project X and other present and future DoD software development projects.

This guidebook describes the Domain Architecture-Based Generation for Ada Reuse (DAGAR) domain architecture and implementation development method. DAGAR has been developed to provide a repeatable, documented method for domain architecture engineering. The method is consistent with the Organization Domain Modeling (0DM) domain engineering method and can be used to support the definition of an asset base architecture and implementation of assets within 0DM. The EDGE/Ada (Enhanced Domain Generation Environment for Ada) toolset provides integrated support for all phases of DAGAR, including automated system generation based on choices selected by the application engineer. The primary purposes of this guidebook are to: (1) Provide a definitive DAGAR reference document which promotes public understanding of the method and its applicability through in-depth descriptions of DAGAR concepts, processes, and workproducts. (2) Provide substantial practical guidance for using the method by describing DAGAR activities and offering examples to get practitioners started.

The Submarine Message Buffer (SMB) is a real, time embedded message processing system developed at the Naval Command, Control and Ocean Surveillance Center, Research, Development, Test and Evaluation Division (NRaD). The SMB is sponsored by the Space and Naval Warfare Systems Command (SPAWAR) to support modernization of SSN (Los Angeles and Seawolf class submarines) radio rooms. The development strategy adopted for the SMB concentrated on the reuse of Ada software. This paper will focus on the design, processes and methodologies, which were used in the development of this system. Metrics will also be provided showing why this system has been identified as an Ada success story by the Ada Joint Program Office among others.

This thesis examines the current Army Program Management software development effort with respect to the application and implementation of software reuse. This study examines current efforts by the Department of Defense and related agencies to implement software reuse into the development and life cycle of both embedded and host application software for automated weapon systems. The DoD software development cycle templates are examined for software reuse applicability, integration, and implementation. Broad overview and analysis of potential, real and perceived reuse implementation inhibitors and barriers is conducted by category (Management, Standards, Library, Legal, and Education), and in conjunction with interviews of critical personnel within the Program Management structure to assess current knowledge and opinion on software reuse. Identified software reuse inhibitors and program personnel concerns are addressed by category, with the intention of finding generalized solutions and application or execution points within the parameters of the software program development structure.

Verification and Validation (V&V) is currently performed during application development for many systems, especially safety-critical and mission- critical systems. The V&V process is intended to discover errors, especially errors related to critical processing, as early as possible during the development process. The system application provides the context under which the software artifacts are validated. This paper describes a framework that extends V&V from an individual application system to a product line of systems that are developed within an architecture-based software engineering environment. This framework includes the activities of traditional application-level V&V, and extends these activities into domain engineering and into the transition between domain engineering and application engineering. The framework includes descriptions of the types of activities to be performed during each of the life-cycle phases, and provides motivation for the activities.

NAS 1.55:3057 Digitized from IA1177307-03-0071 , IA1177307-03-0072 .

Reuse of products, processes and knowledge will be the key to enable the software industry to achieve the dramatic improvement in productivity and quality required to satisfy the anticipated growing demand. Although experience shows that certain kinds of reuse can be successful, general success has been elusive. A software life-cycle technology which allows broad and extensive reuse could provide the means to achieving the desired order-of-magnitude improvements. The scope of a comprehensive framework for understanding, planning, evaluating and motivating reuse practices and the necessary research activities is outlined. As a first step towards such a framework, a reuse-enabling software evolution environment model is introduced which provides a basis for the effective recording of experience, the generalization and tailoring of experience, the formalization of experience, and the (re-)use of experience.

Reuse of products, processes and knowledge will be the key to enable the software industry to achieve the dramatic improvement in productivity and quality required to satisfy the anticipated growing demand. Although experience shows that certain kinds of reuse can be successful, general success has been elusive. A software life-cycle technology which allows broad and extensive reuse could provide the means to achieving the desired order-of-magnitude improvements. The scope of a comprehensive framework for understanding, planning, evaluating and motivating reuse practices and the necessary research activities is outlined. As a first step towards such a framework, a reuse-enabling software evolution environment model is introduced which provides a basis for the effective recording of experience, the generalization and tailoring of experience, the formalization of experience, and the (re-)use of experience.

Thesis advisor(s): Norman F. Schneidewind

This paper addresses nontechnical barriers inhibiting the insertion of software reuse technology for the Strategic Defense Initiative (SDI). The paper provides a brief overview and definition of software reuse and its benefits, and an assessment is presented of the current state of practice of software reuse. Based on this foundation, factors currently inhibiting software reuse are identified and a strategy for encouraging reuse within the SDI program is presented. Nontechnical barriers that are addressed include the lack of financial incentives, organizational difficulties, and the lack of specific contractural mechanisms. Mechanisms for implementing the software reuse strategy are realized in the form of additions and changes to the Request for Proposal (RFP) and contract language. Incentives for software reuse and guidelines for evaluating contractor proposals with respect to reuse are also discussed.

Recent events, the DOD Software Master Plan and the new DARPA initiatives, have indicated a renewed interest in DOD to implement an effective software reuse program. Although this goal was attempted previously, it met with poor results. Three possible explanations of why reuse has not become a viable practice in the DOD were posited. The first explanation was that reuse in the DOD failed because there was no single higher order language; the second explanation was that reuse failed solely because of the barriers inhibiting it; and the hypothesized explanation was that reuse failed because DOD did not follow an adequate change strategy based on a change model from organizational design literature. The literature was examined in light of the three possible explanations, and a telephone survey was performed to gain further evidence from personnel, both inside and outside the DOD, that are involved in reuse connected with the DOD. The results of the phone survey were analyzed in a qualitative manner based on the literature review, and then each possible explanation was analyzed against both the literature and survey results. The hypothesized explanation was deemed to provide the best fit.

Recent events, the DOD Software Master Plan and the new DARPA initiatives, have indicated a renewed interest in DOD to implement an effective software reuse program. Although this goal was attempted previously, it met with poor results. Three possible explanations of why reuse has not become a viable practice in the DOD were posited. The first explanation was that reuse in the DOD failed because there was no single higher order language; the second explanation was that reuse failed solely because of the barriers inhibiting it; and the hypothesized explanation was that reuse failed because DOD did not follow an adequate change strategy based on a change model from organizational design literature. The literature was examined in light of the three possible explanations, and a telephone survey was performed to gain further evidence from personnel, both inside and outside the DOD, that are involved in reuse connected with the DOD. The results of the phone survey were analyzed in a qualitative manner based on the literature review, and then each possible explanation was analyzed against both the literature and survey results. The hypothesized explanation was deemed to provide the best fit.

This memorandum provides an overview of the software reuse process for the Naval Undersea Warfare Center Division Newport. The three primary areas of the process that are addressed are the domain analysis, reuse software design metrics, and re-engineering software for reuse.

Social computing has the potential to contribute to scientific research. Ongoing developments in information and communications technology improve capabilities for enabling scientific research, including research fostered by social computing capabilities. The recent emergence of e-Science practices has demonstrated the benefits from improvements in the technological infrastructure, or cyber-infrastructure, that has been developed to support science. Cloud computing is one example of this e-Science trend. Our own work in the area of software reuse offers methods that can be used to improve new technological development, including cloud computing capabilities, to support scientific research practices. In this paper, we focus on software reuse and its potential to contribute to the development and evaluation of information systems and related services designed to support new capabilities for conducting scientific research.

This document describes the services provided by the prototype Software Reuse Environment, which was developed by CTA for NASA Goddard Space Flight Center, Code 520. This is one of three guides delivered by CTA as part of the environment. The other two guides are: Software Generation and Installation Guide; and SEMANTX--Defining the Schema. The Software Generation and Installation Guide describes the software source modules that make up the Reuse Environment, with instructions on how to generate and install an executable system from the source code. SEMANTX--Defining the Schema describes how a reuse database is created. Actually this guide is more general than the reuse database, as it describes how to generate a SEMANTX database. SEMANTX is an off-the-shelf tool that we have used to implement the reuse database. It is a product of Semantyk Systems, Inc. The Software Reuse Environment is built upon SEMANTX as well as on the IDE Structured Analysis Integrated Environment. (IDE is Interactive Development Environments, Inc.) SEMANTX itself is built on top of the Unify Database Management System. To use the Software Reuse Environment you should have the User's Manuals for SEMANTX, for Unify, and for the IDE software. CTA has provided all of these with the environment.

This document describes 3rd year accomplishments and summarizes overall project accomplishments. Included as attachments are all published papers from year three. Note that the budget for this project was discontinued after year two, but that a residual budget from year two allowed minimal continuance into year three. Accomplishments include initial investigations into log-file based reverse engineering, service-based software reuse, and a source to XML generator.

One way to increase the quality of software products and the productivity of software development is to reuse existing software components when building new software systems. In order to monitor improvements in reuse, the level of reuse must be measured. In this NASA supported project we (1) derived a suite of metrics which quantify reuse attributes for object oriented, object based, and procedural software, (2) designed prototype tools to take these measurements in Ada, C++, Java, and C software, (3) evaluated the reuse in available software, (4) analyzed the relationship between coupling, cohesion, inheritance, and reuse, (5) collected object oriented software systems for our empirical analyses, and (6) developed quantitative criteria and methods for restructuring software to improve reusability.

Includes bibliographical references (p. 466-479) and index

In this article, we present the challenge of software citation as a method to ensure credit for and identification, discovery, and reuse of software in scientific and engineering research. We discuss related work and key challenges/research directions, including suggestions for metadata necessary for software citation.

V&V is currently performed during application development for many systems, especially safety-critical and mission-critical systems. The V&V process is intended to discover errors, especially errors related to entire' domain or product line rather than a critical processing, as early as possible during the development process. The system application provides the context under which the software artifacts are validated. engineering. This paper describes a framework that extends V&V from an individual application system to a product line of systems that are developed within an architecture-based software engineering environment. This framework includes the activities of traditional application-level V&V, and extends these activities into the transition between domain engineering and application engineering. The framework includes descriptions of the types of activities to be performed during each of the life-cycle phases, and provides motivation for activities.