leff@smu.UUCP (Laurence Leff) (02/23/89)
These reports are available from Technical Information Center (DTIC) and the
National Technical Information Service (NTIS). To obtain a copy of any of the
reports, please contact DTIC or NTIS directly, providing them with the ADA
number for the desired report. (For example, _ADA169705_ is the DTIC number
for the SEI report _Toward a Reform of the Defense Department Software
Acquisition Policy_.)
Software Engineering Institute Carnegie Mellon University
Information Management
Pittsburgh, Pennsylvania 15213
1 January 1987 -- 31 December 1987 Annotated list of available documents
for public release.
Defense Technical Information Center (DTIC)
ATTN: FDRA
Cameron Station
Alexandria VA 22304-6145
National Technical Information Service (NTIS)
U.S. Department of Commerce
Springfield, VA 22161
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1987 Technical Reports
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ADA180905
Weiderman, Habermann, Borger, Klein, M., Landherr, Smeaton, Altman,
D'Ippolito, Kochmar, Sun
Evaluation of Ada Environments
The full report provides a detailed description of the methodology and examples
of its usage. Chapter 1 gives an extended cross-environment analysis of the
results of the project. For each of five experiment groups, it compares three
APSEs. The chapter provides an overview of the results of all the experiments
and is written for the technical manager. Chapter 2 describes in detail the
methodology used for evaluating the environments, along with some of the
background information and references to previous work in environment
evaluation. Chapters 3 through 8 provide detailed descriptions of the six
experiment groups. Here one can find the information on particular criteria,
questions, and life cycle activities that were tested for each experiment, as
well as test scripts, checklists, and resulting data that were collected.
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ADA178971
Martin A., Deasy
The Effect of Software Support Needs on DoD Software Acquisition
Policy: Part 1: A Framework for Analyzing Legal Issues
This report summarizes the significant technical and managerial considerations
that affect the maintenance and enhancement of software. Prior work suggested
that it is often in the acquisition of intellectual property needed to maintain
and enhance software that data rights disputes arise between DoD and the
private sector. For this reason, an understanding of DoD's maintenance and
enhancement requirements is a necessary predicate toward shaping a data
rights/software acquisition policy that achieves the proper balance between the
intellectual property needs of DoD and the proprietary interests of private
industry. A survey of software engineering literature revealed no study that
addressed this important subject. Accordingly, the Software Licensing Project
undertook to examine the issue itself. Although this report discusses
technical and managerial issues, it is principally intended as a guide for
lawyers and policymakers who deal with, and have regulatory responsibility for,
software and data rights acquisition issues.
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ADA178178
Johnson
SEI Software Engineering Education Directory
The purpose of this directory is twofold. First, it should help people make
rational choices among software engineering courses and software engineering
degree programs by presenting a detailed listing of what courses and programs
are available. The other major purpose is to establish contact between the SEI
and the institutions which offer these courses and programs.
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ADA182982
Druffel, Wood, Pethia, Greenberger, Shuba
Software and System Warranty Issues
This report addresses technical and administrative issues associated with the
system warranty process, and recommends a straightforward, two-page generic
system warranty clause that covers software, not in isolation, but as part of a
warranted system. The report describes one approach to relieving problems of
system failure, and addresses legal, technical, and administrative issues that
support warranty enforcement. The goal is to ease the government's burden of
proving the existence of a defect for which the warranty clause provides a
remedy. The key to satisfying that goal is to develop technical tests and
specifications that provide objective and demonstrable standards against which
a claim for breach of warranty can be measured.
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ADA181853
Cooper
Distributed Systems Technology Survey
This report is one of a series of survey reports. It is not intended to
provide an exhaustive discussion of topics pertinent to the area of distributed
systems technology. Rather, it is intended as an informative review of the
technology surveyed. These surveys were conducted in late 1985 and early 1986.
One of the core technology areas in which project members were interested is
distributed systems technology. This report surveys the technical issues
involved in designing distributed systems, with particular emphasis on those
aspects that affect software engineering environments.
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ADA181852
Feiler
User Interface Technology Survey
This report is one of a series of survey reports. It is not intended to
provide an exhaustive discussion of topics pertinent to the area of distributed
systems technology. Rather, it is intended as an informative review of the
technology surveyed. These surveys were conducted in late 1985 and early 1986.
One of the core technology areas in which project members conducted a survey
was user interface technology. This report attempts to do two things: specify
an understanding of user interfaces by presenting a taxonomy that encompasses
the various aspects of user interfaces, and indicate the state of the
technology today by highlighting some of the major issues.
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ADA181156
Newcomer
Tool Interface Technology
This report is one of a series of survey reports. It is not intended to
provide an exhaustive discussion of topics pertinent to the area of user
interface technology. Rather, it is intended as an informative review of the
technology surveyed. These surveys were conducted in late 1985 and early 1986.
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ADA182003
Ford, Gibbs, Tomayko
Software Engineering Education: An Interim Report from the Software
Engineering Institute
The goals and activities of the Software Engineering Institute's Education
Program are described. Two curriculum recommendations are presented, one for a
professional Master of Software Engineering degree program, and the other for
an undergraduate project course in software engineering. Also presented is an
organizational structure for software engineering curriculum content.
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ADA182023
Foreman, Goodenough
Ada Adoption Handbook
The Ada Adoption Handbook provides program managers with information about how
best to tap Ada's strengths and manage this new software technology. Although
the issues are complex, they are not all unique to Ada. Indeed, many of these
issues must be addressed when using any language for building sophisticated
systems. The handbook addresses the advantages and risks inherent in adopting
Ada. Significant emphasis has been placed on providing information and
suggesting methods that will help program and project managers succeed in
adopting Ada across a broad range of application domains.
The handbook focuses on the following topics: program management issues
including costs and technical and program control; Ada's goals and benefits;
software tools with emphasis on compiler validation and quality issues; the
state of Ada technology as it relates to system engineering; the application of
special purpose languages; issues related to mixing Ada with other languages;
possible productivity benefits resulting from software reuse; and implications
for education and training.
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ADA182895
Firth, Mosley, Pethia, Roberts, Wood, W.
A Guide to the Classification and Assessment of Software Engineering Tools
Software engineering tools are computer programs that assist people in doing
the work of software engineering. As understanding of the software engineering
process has broadened and the need to solve problems has intensified, there has
been increasing interest in using software engineering tools. Understanding
what a tool does and comparing it to similar tools are difficult tasks given
the diversity of functionality that exists. This report describes a tool
classification technique that helps those investigating tools decide where a
tool fits in the software engineering process and identify what a tool does or
doesn't do. It also provides guidance to the tool evaluation process and lists
specific criteria that should be considered when evaluating tools.
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ADA182895
Humphrey
Characterizing the Software Process: A Maturity Framework
Improvement in the performance of software development organizations is an
essential national need. The improvement process has five basic elements: 1.
an understanding of the current status of the development process, 2. a vision
of the desired process, 3. a prioritized list of required improvement actions,
4. a plan to accomplish these actions, and 5. the resources and commitment to
execute the plan. This paper addresses the first three of these elements by
providing a model for software organizational improvement. The structure of
this model provides five maturity levels, identifies the key improvements
required at each level, and establishes a priority order for implementation.
This model has been tested with a number of organizations and found to
reasonably represent the status and needs of actual software development
groups.
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ADA185742
A. Martin, Deasy
Seeking the Balance between Government and Industry Interests
in Software Acquisition. Volume I. A Basis for
Reconciling DoD and Industry needs for Rights in Software
The policy under which the Department of Defense (DoD) acquires rights in
software and technical data has, in the past, been imbalanced in the direction
of obtaining more rights than necessary to meet its needs. As noted by the
Packard Commission, a more balanced policy is in the interests of both the DoD
and industry. The DoD has recently adopted a new policy for acquiring rights
in technical data, and is developing a separate policy for acquiring rights in
software. This report offers several recommendations for achieving a balanced
policy as to government funded software, privately funded software, and mixed
funding software that will meet the mission needs of the DoD while enabling
contractors to protect their proprietary interests, and commercialize their
software products.
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ADA200601
Meyers, Cappellini
The Use of Representation Clauses and Implementation-Dependent Features in
Ada: I. Overview
This report, the first in a series, presents an overview of the aspects of the
Ada language relating to representation clauses and implementation-dependent
features. Particular emphasis is given to the use of Ada for application to
packed data structures. This report is in part tutorial, and several examples
from real-time, mission-critical systems are discussed in detail. A brief
discussion of design guidelines for the use of representation clauses and
implementation-dependent features is included.
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ADA188925
Meyers, Cappellini
The Use of Representation Clauses and Implementation-Dependent Features in
Ada: IIA. Evaluation Questions
This report is the second in a series on the use of representation clauses and
implementation-dependent features in Ada. It is the purpose of this document
to specify a set of questions relevant to the assessment of the support of
representation clauses and implementation-dependent features provided by an Ada
compiler. The questions identified are categorized according to functionality
and address both qualitative and quantitative aspects.
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ADA183429
Humphrey, Kitson
Preliminary Report on Conducting SEI-Assisted Assessments of Software
Engineering
Characterizing the state of software engineering practice within an
organization is a necessary prerequisite to orderly, meaningful, and
sustainable improvement of the organizations ability to produce or support
cost-effective, high quality software products. The Software Engineering
Institute (SEI) is developing a methodology for conducting SEI-assisted
assessments of software engineering capability. The assessment methodology has
five phases: 1. selecting the candidate organization, 2. preparing for the
assessment, 3. conducting the assessment, 4. communicating final assessment
findings and action recommendations, and 5. post-assessment follow-up
activities. This report describes the methodology in detail.
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ADA188926
Meyers, Cappellini
The Use of Representation Clauses and Implementation-Dependent Features in
Ada: IIIA. Qualitative Results for VAX Ada
This report, one in a series, provides a qualitative assessment of the support
of representation clauses and implementation-dependent features in Ada provided
by the VAX Ada compiler, Version 1.3. The evaluation questions that were
presented in a previous report of this series form the basis of the qualitative
assessment. A subjective evaluation of the support provided for these features
is also presented.
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ADA200602
Meyers, Cappellini
The Use of Representation Clauses and Implementation-Dependent Features in
Ada: IIB. Experimental Procedures
This report is one in a series dealing with the use of representation clauses
and implementation-dependent features in Ada. The purpose of this report is to
discuss detailed experimental procedures to assess compiler support. It is
readily acknowledged that the domain of possible experimentation is large. To
facilitate the experimentation, a methodology is proposed that relies on
program generators and automated analysis tools. An example of the methodology
is presented in some detail.
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ADA200603
Tomayko
Teaching a Project Intensive Introduction to Software Engineering
This report is meant as a guide to the teacher of the introductory course in
software engineering. It contains a case study of a course based on a large
project. Other models of course organization are also discussed. Additional
materials used in teaching the course and samples of student-produced
documentation are also available.
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ADA185697
Altman, Weiderman
Timing Variation in Dual Loop Benchmarks
Benchmarks that measure time values using a standard system clock often employ
a dual loop design. One of the important assumptions of this design is that
textually identical loop statements will take the same amount of time to
execute. This assumption was tested on two bare computers with Ada test
programs and has been demonstrated to be inaccurate in these specific test
cases.
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ADA187231
Altman
Factors Causing Unexpected Variations in Ada Benchmarks
Benchmarks are often used to describe the performance of computer systems.
This report considers factors that may cause Ada benchmarks to produce
inaccurate results. Included are examples from the ongoing benchmarking
efforts of the Ada Embedded Systems Testbed (AEST) Project using bare target
computers with several Ada compilers.
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ADA187230
Humphrey, Sweet
A Method for Assessing the Software Engineering Capability of Contractors
This document provides guidelines and procedures for assessing the ability of
potential DoD contractors to develop software in accordance with modern
software engineering methods. It includes specific questions and a method for
evaluating the results.
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ADA200542
Dart, Ellison, Feiler, Habermann
Software Development Environments
"Environment" refers to the collection of hardware and software tools that a
system developer uses to build software systems. As technology improves and
user expectations grow, an environment's functionality tends to change. Over
the last 20 years, the set of software tools available to developers has
expanded considerably. We can illustrate this change by observing some
distinctions in the terminology. "Programming environment" and "software
development environment" are often used synonymously, but here we make a
distinction between the two.
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ADA200611
Klein, D., Firth
Final Evaluation of MIPS M/500 Final Report for the RISC Insertion Project
In response to a request from the DoD, an analysis of a Reduced Instruction Set
Computer (RISC) processor, the MIPS M/500, was performed. All aspects of
processor capabilities and support software were evaluated, tested, and
compared to familiar Complex Instruction Set Computer (CISC) architectures. In
all cases, the RISC computer and its support software performed better than a
comparable CISC computer. This report provides the general and specific results
of these analyses, along with the recommendation that the DoD and other
government agencies seriously consider this or other RISC architectures as a
highly viable and attractive alternative to the more familiar but less
efficient CISC architectures.
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ADA191096
Weiderman, Borger, Cappellini, Dart, Klein, M., Landherr
Ada for Embedded Systems: Issues and Questions
This report addresses issues and questions related to the use of Ada for
embedded systems applications; it contains some preliminary recommendations for
compilation system implementors, application developers, program managers, and
Ada policy makers. The issues and questions provide the context for the
Real-Time Embedded Systems Testbed (REST) Project at the SEI, where staff
members are investigating software development and performance issues for
real-time embedded systems.
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ADA200607
Donohoe
Ada Performance Benchmarks on the MicroVAX II: Summary and Results
This report documents the results obtained from running the University of
Michigan and the ACM SIGAda Performance Issues Working Group (PIWG) Ada
performance benchmarks on a DEC VAXELN MicroVAX II using the DEC VAXELN Ada
compiler. A brief description of the benchmarks and the test environment is
followed by a discussion of some problems encountered and lessons learned. The
output of each benchmark program is also included.
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ADA200608
Donohoe
A Survey of Real-Time Performance Benchmarks for the Ada Programming
Language
This survey provides a summary description of some of the major Ada benchmarks
currently available and an evaluation of their applicability to the Real-Time
Embedded Systems Testbed Project at the SEI. The benchmarks discussed are the
University of Michigan benchmarks, the ACM Performance Issues Working Group
(PIWG) benchmarks, and the prototype Ada Compiler Evaluation Capability (ACEC)
of the Institute for Defense Analyses (IDA).
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ADA188100
Mark Borger
VAXELN Experimentation: Programming a Real-Time Clock and Interrupt Handling
Using VAXELN Ada 1.1
This report describes the results of implementing an interrupt handler totally
in Ada for a MicroVAX II/VAXELN 2.3 target system, the VAXELN 1.1 Ada compiler,
and a KWV11-C programmable real-time clock. It provides an overview of VAXELN
interrupt handlers and the operation of the real-time clock; discusses and
demonstrates the use of VAXELN kernel services to establish a link between the
clock's interrupt and the starting address of an interrupt service routine;
presents an Ada package of interfaces to the KWV11-C device; provides Ada
source code examples demonstrating the use of this package; and presents
relevant observations, recommendations, and measurement results.
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ADA188932
Weiderman
Criteria for Constructing and Using an Ada Embedded System Testbed
The purpose of this report is to list some of the criteria used in five aspects
of the project: the hardware configuration, the software configuration, the
real-time application, the Ada real-time experiments, and the benchmarking and
instrumentation techniques. Each criterion will include a rationale. Each of
the criteria listed in this report will be categorized as either essential,
highly desirable, or desirable.
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ADA200609
Weiderman, et al.
Annual Technical Report for Ada Embedded Systems Testbed Project
The purpose of the Ada Embedded Systems Testbed Project (now called the
Real-Time Embedded Systems Project) is to investigate some of the critical
issues in using Ada for real-time embedded applications, particularly the
extent and quality of the runtime support facility provided by Ada
implementations. The project's objective has been to generate new information
about using Ada in real-time embedded systems. This information is in the form
of benchmark test results, higher level experiment results, and lessons learned
in designing and implementing real-time applications in Ada. This technical
report provides an overview of the results produced in the first year of the
project (through September 30, 1987). Details of these results are contained in
other referenced technical reports.
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ADA200612
Borger
VAXELN Experimentation: Programming a Real-Time Periodic Task Dispatcher
Using VAXELN Ada 1.1
The purpose of this paper is to provide the reader with some technical
information and observations, Ada source code, and measurement results based on
experimentation with respect to developing a real-time periodic task dispatcher
in Ada. In this context, a periodically scheduled task set implies that each
task in the set is executed at its own fixed frequency; a periodic task
dispatcher is a software component that schedules the individual tasks at their
implied runtime frequency. The results presented here are specific to a
MicroVAX-II/VAXELN 2.3 target system, the VAXELN 1.1 Ada compiler, and a
KWV11-C programmable real-time clock. Specifically, these results provide
answers to the question: How can one achieve the effect of scheduling a set of
periodic Ada tasks when the runtime frequency of some of the individual tasks
is less than the clock-cycle frequency supported by an Ada runtime
implementation?
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ADA200604
Landherr, Klein, M.,
Inertial Navigation System Simulator: Behavioral Specification
The Real-Time Embedded Systems Testbed Project at the SEI is specifying and
developing a representative real-time application. This document augments an
original set of specifications written by a Navy affiliate. The purpose of this
behavioral specification is to clarify and augment the original.
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ADA200605
M. Klein, Landherr
Inertial Navigation System Simulator Program: Top-Level Design
A real-time Ada application, an Inertial Navigation System (INS) simulator, is
being developed by the Real-Time Embedded Systems Testbed Project as a vehicle
to analyze issues regarding the use of Ada in the real-time embedded domain and
to provide a context for future experimentation. The technical philosophy
behind developing a real-time Ada artifact is to: (1) select a representative
(e.g., strict timing demands, multiple concurrent activities, low-level I/O,
error handling, interrupts, and periodic activities) real-time application; (2)
use Ada tasks as the unit of concurrency for the real-time design; and (3)
apply any relevant practical results being produced by the real-time scheduling
research community. In particular, the INS simulator must satisfy a set of
timing requirements that are similar to an INS with respect to data updating,
message transmission, and message reception. This document discusses the
top-level design of this application from three points of view: data flow
perspective, concurrency and control perspective, and the Ada module
perspective.
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ADA188928
Van Scoy
Prototype Real-Time Monitor: Executive Summary
This report summarizes the history, goals, and conclusions of the prototype
real-time monitor development effort. This effort was undertaken to address two
specific technical questions: 1) How can user tools find, access, and display
data hidden in the bodies of Ada applications? 2) How can user tools be layered
on top of Ada applications? The effort resulted in a generally usable
prototype, which is documented by four other SEI reports (CMU/SEI-87-TR-36
through CMU/SEI-87-TR-39).
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ADA188929
D'Ippolito, Lee, K., Plinta, Rissman, Van Scoy
Prototype Real-Time Monitor: Requirements
The requirements imposed by flight simulators and good software engineering
practice on Ada systems force software engineers to seek new solutions to the
problem of monitoring executing software. This report examines some of these
requirements and, based on these requirements, defines a subset for
implementation as a prototype real-time monitor (RTM).
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ADA188930
Van Scoy, Plinta, Coddington, T., D'Ippolito, Lee, K.
Prototype Real-Time Monitor: User's Manual
This report defines the user interface to the prototype real-time monitor
(RTM). It defines the concepts and commands needed by a software engineer to
use the RTM. In addition to defining the user interface, the report explains
the steps needed to tailor the RTM to work with the user's application.
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ADA188931
Van Scoy, Plinta, D'Ippolito, Lee, K., Rissman
Prototype Real-Time Monitor: Design
This report describes the software design used to implement the prototype
real-time monitor requirements. The design is presented at three levels:
system level, object level, and package architecture level. The report
concludes with a discussion of the key implementation obstacles that had to be
overcome to develop a working prototype: determining system addresses,
communicating with an executing application, accessing application memory,
converting data into human-readable form, and distributed CPU architectures.
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ADA191095
Van Scoy
Prototype Real-Time Monitor: Ada Code
This report documents the Ada code of the prototype real-time monitor.
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ADA200610
Donohoe
Ada Performance Benchmarks on the Motorola MC68020: Summary and Results
This report documents the results obtained from running the ACM SIGAda
Performance Issues Working Group (PIWG) and the University of Michigan Ada
performance benchmarks on a Motorola MC68020 microprocessor (MVME133 VMEmodule
Monoboard Microcomputer), using the Systems Designers Ada-Plus, the TeleSoft
TeleGen2, and the Verdix VAX/VMS hosted cross-compilers. A brief description of
the benchmarks and the test environment is followed by a discussion of some
problems encountered and lessons learned. Wherever possible, the output of each
benchmark program is also included.
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ADA200606
Firth, Wood, Pethia, Roberts, Mosley, Dolce
A Classification Scheme for Software Development Methods
Software development methods are used to assist with the process of designing
software for real-time systems. Many such methods have come into practice over
the last decade, and new methods are emerging. These new methods are more
powerful than the old ones, especially with regard to real-time aspects of the
software. This report describes a classification scheme for software
development methods, includes descriptions of the major characteristics of such
methods, and contains some words of advice on choosing and applying such
methods.
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ADA199877
Hefley
Issues in Software: A Blue Two Visit Feasibility Assessment
The SEI participated in a series of fact-finding meetings sponsored by the Air
Force Coordinating Office for Logistics Research to gather information
necessary to set the scope for and to implement one or more Blue Two Visits on
software. The purpose of a Blue Two Visit (BTV) is to introduce to industry's
top design engineers and program managers the day-to-day constraints Air Force
maintainers face on front-line operations bases. The participants experience
first-hand the effects of design on maintenance. This exposure has been
significant in bridging the gap between DoD and industry in understanding,
documenting, and supporting Air Force weapon system requirements to increase
combat supportability. This report documents discussions that attempt to
address the following questions for a software-oriented BTV: 1) Do software
maintainers and users have messages for software designers and programmers? 2)
What are these messages? 3) How can these messages be best communicated? 4) To
whom should these messages be targeted? 5) What should the BTV be called?
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ADA191097
Lee, Rissman, D'Ippolito, Plinta, Van Scoy
An OOD Paradigm for Flight Simulators
This report presents a paradigm for object-oriented implementations of flight
simulators. It is a result of work on the Ada Simulator Validation Program
(ASVP) carried out by members of the technical staff at the SEI.
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ADA188927
Ford, editor
Report on the SEI Workshop on Ada in Freshman Courses
The Undergraduate Software Engineering Education Project of the SEI Education
Program sponsored a workshop on Ada in Freshman Courses in June 1987. The
workshop brought together several educators to discuss how the software
engineering content of beginning programming and data structures courses might
be improved. This report describes the workshop and summarizes the discussions
and conclusions, and it also includes the position papers prepared by the
participants.
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ADA188923
Nestor
Views for Evolution in Programming Environments
Programming environments have become a focal point for much of the work
directed toward improving the practice of software engineering. Such
environments must provide mechanisms for recording and organizing the complex
set of persistent technical and management data associated with all parts of
the life cycle of large software systems. This paper focuses on one important
aspect of such persistent data: how to allow evolution when the existing
information must be preserved without change to maintain history. First, the
role of history in programming environments is discussed. Next, the additional
demands of evolution are considered and shown to lead to a set of problems.
View mechanisms are suggested as a solution to the problems. A simple example
involving file system directory structure is presented to illustrate these
problems. A simple view mechanism, called multidirectories, is introduced and
shown to solve the illustrated problems.
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ADA188924
Nestor
Evolving Persistent Objects in a Distributed Environment
This paper considers a class of objects, called incrementally mutable objects,
that are intermediate between mutable and immutable objects. Intuitively, the
only permitted modifications to an incrementally mutable object are those that
add new information to the object while preserving existing information.
Changes to incrementally mutable objects do not require central
synchronization. When a network becomes partitioned, the same incrementally
mutable object can be safely modified in each subnetwork. A mutable object can
be modeled by a set of immutable objects that represent each value of the
object over time and an incrementally mutable object that relates each
immutable object to its successor. Multiple successors are permitted to
represent parallel changes.
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ADA188922
Stone, Nestor
IDL: Background and Status
This paper presents an overview of the Interface Description Language (IDL).
We describe the language and its history. We also discuss the status of the IDL
community.
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ADA199634
Engle, Firth, Graham, Wood, B.
Interfacing Ada and SQL
The SEI was asked by the Ada Joint Program Office to investigate the problem of
interfacing programs written in Ada with database management systems
implementing the SQL database language. The authors decided to concentrate on a
description of the problems involved in producing an interface that would be
worthy of becoming a standard. This document is meant to assist the reader in
answering the question "What constitutes a good interface between Ada and SQL?"
The document should be useful both in the production of a standard and in the
analysis of any proposed standard.
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--
Carnegie Mellon University
Software Engineering Institute
(412) 268-6378