AdaIC News Spring/Summer 1996
Comparison Shows Ada with Twice the
Cost Effectiveness of C Over Lifecycle
Lifecycle costs are a major problem for software development, and a major factor in comparing languages. But where do you find real-world test cases where conditions are the same for the languages under study? One such case was work on the Verdix Ada Development System (VADS) -- where work in C began in 1983, before suitable Ada compilers were available. Later, both C and Ada were used. The VADS tools, supporting both C and Ada, were used for their own development, and the staff was equally proficient in both languages.
"Comparing Development Costs of C and Ada", by Dr. Stephen F. Zeigler (now with Rational Software Corp.) looks at the update/maintenance records of the Verdix system. The conclusion is that over the lifecycle, Ada's cost effectiveness is two times or better than C's.
One interesting conclusion was that, within a six-month timeframe, Ada is not more difficult to learn than is C; and as developers continue to learn Ada, their code will improve in quality. In contrast, the study found that the fix rates of C users do not substantially improve after the first six months. "We can observe that those people who code primarily in Ada can expect fewer bugs and general improvement, while C users can expect harder going," the study reported.
[The Ada Information Clearinghouse has Dr. Zeigler's report both in hardcopy and over the World Wide Web.
Army Reuse Center Offers Tool to Support Domain Engineering
The Army Reuse Center (ARC) has developed the Domain Knowledge Database (DKDB), an automated tool that supports domain engineering.
The DKDB allows managers to identify and control domain-related reusable assets, and allows engineers to store, manage, and manipulate the domain knowledge obtained through reuse analysis. In addition, the tool provides valuable information for selecting and classifying reusable assets that are targeted for installation into a domain reuse library.
["Automation Support for Domain Engineering," The Army Reuse Center News, December 1995 (Vol. 4, No. 4). The Army Reuse Center, Department of the Army, USAISSC, Attn: ASQB IRC Stop C 2, Fort Belvoir, VA 22060-5576; 703/806-4300.
The Reuse Center News article also provides an overview of the domain-engineering process from domain analysis to domain design to domain implementation.]
Reuse in the Defense System Management College
In another article, the Army Reuse Center News interviewed Sherwin J. Jacobson, Professor of Engineering Management in the Software Management Department at the Defense System Management College (DSMC).
Jacobson discussed the role of software reuse in the DSMC's educational effort as important in helping change the culture within the DoD from developing unique software from scratch to one of dealing with the concept of developed components that are integrated into a total system. The DSMC has incorporated the issue of software reuse into several courses, including both basic and advanced acquisition and program-management courses.
["Reuse from an Educator's Perspective," The Army Reuse Center News, December 1995 (Vol. 4, No. 4)]
Ada 95 Bindings Preserve GCCS Investment
The December 1995 issue of the STARS Newsletter describes an Intermetrics/Boeing effort to combine ProtoTech and STARS technology to provide a set of Ada 95 bindings for the block 1 common core services of the Global Command and Control System (GCCS). (These services, in essence, are a library of middleware functions that are common to many command and control -- C2 -- systems. The services of this middleware are implemented as an infrastructure on top of Unix and X-Windows/Motif.)
The effort will develop a proof-of-concept demonstration using these bindings by converting to Ada 95 a C application that uses the GCCS core services, proving that it operates as it did before the transition. It will also collect metrics that will provide insight into the comparative characteristics of an identical application in the C programming language and Ada 95, and provide early identification of issues moving to Ada 95.
["Ada 95 Bindings Preserve Global Command and Control System Investment," Casey Fung, STARS Newsletter, December 1995.]
Ada Used to Upgrade Air Traffic Control System
The Loral Corp. has used Ada in its upgrade of the nation's air traffic control system. The software, released in November, is designed to run new advanced computer workstations that will replace old displays and computers.
Loral Air Traffic Control of Rockville, Md., released software written primarily in Ada and consisting of about 441,000 source lines of code for the Display System Replacement (DSR) program, and also finished software for the DSR support system, with an additional 136,000 source lines of Ada.
The DSR was approved in September 1995 by the Federal Aviation Administration. Common system interfaces, communications networks and operational procedures will link facilities to support the FAA's En Route Air Traffic Control mission.
["Loral finishes air traffic control code," John Keller, Military and Aerospace Electronics, January 1996.]
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