Embedded, Everywhere: A Research Agenda for Networked Systems of Embedded Computers

236 Pages·2001·1.14 MB·English

by  National Research Council

Embedded, Everywhere
A Research Agenda for
Networked Systems of Embedded Computers
Committee on Networked Systems of Embedded Computers
Computer Science and Telecommunications Board
Division on Engineering and Physical Sciences
National Research Council
NATIONAL ACADEMY PRESS
Washington, D.C.
NOTICE: The project that is the subject of this report was approved by the Gov-
erning Board of the National Research Council, whose members are drawn from
the councils of the National Academy of Sciences, the National Academy of Engi-
neering, and the Institute of Medicine. The members of the committee responsible
for the report were chosen for their special competences and with regard for
appropriate balance.
Support for this project was provided by the Defense Advanced Research Projects
Agency and the National Institute of Standards and Technology. Any opinions,
findings, conclusions, or recommendations expressed in this material are those of
the authors and do not necessarily reflect the views of the sponsor. Moreover, the
views, opinions, and findings contained in this report should not be construed as
an official Department of Defense position, policy, or decision, unless so desig-
nated by other official documentation.
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National Research Council
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COMMITTEE ON NETWORKED SYSTEMS OF
EMBEDDED COMPUTERS
DEBORAH L. ESTRIN, University of California at Los Angeles, Chair
GAETANO BORRIELLO, University of Washington
ROBERT PAUL COLWELL, Intel Corporation
JERRY FIDDLER, Wind River Systems, Inc.
MARK HOROWITZ, Stanford University
WILLIAM J. KAISER, Sensoria Corporation
NANCY G. LEVESON, Massachusetts Institute of Technology
BARBARA H. LISKOV, Massachusetts Institute of Technology
PETER LUCAS, Maya Design Group
DAVID P. MAHER, InterTrust Technologies Corporation
PAUL M. MANKIEWICH, Lucent Technologies
RICHARD TAYLOR, Hewlett-Packard Laboratories
JIM WALDO, Sun Microsystems, Inc.
Staff
LYNETTE I. MILLETT, Program Officer (Study Director beginning
September 2000)
JERRY R. SHEEHAN, Senior Program Officer (Study Director through
August 2000)
SUZANNE OSSA, Senior Project Assistant
v
COMPUTER SCIENCE AND TELECOMMUNICATIONS BOARD
DAVID D. CLARK, Massachusetts Institute of Technology, Chair
DAVID BORTH, Motorola Labs
JAMES CHIDDIX, AOL Time Warner
JOHN M. CIOFFI, Stanford University
ELAINE COHEN, University of Utah
W. BRUCE CROFT, University of Massachusetts at Amherst
SUSAN L. GRAHAM, University of California at Berkeley
JUDITH HEMPEL, University of California at San Francisco
JEFFREY M. JAFFE, Bell Laboratories, Lucent Technologies
ANNA KARLIN, University of Washington
MICHAEL KATZ, University of California at Berkeley
BUTLER W. LAMPSON, Microsoft Corporation
EDWARD D. LAZOWSKA, University of Washington
DAVID LIDDLE, U.S. Venture Partners
TOM M. MITCHELL, WhizBang! Labs, Inc.
DONALD NORMAN, UNext.com
DAVID A. PATTERSON, University of California at Berkeley
HENRY (HANK) PERRITT, Chicago-Kent College of Law
BURTON SMITH, Cray, Inc.
TERRY SMITH, University of California at Santa Barbara
LEE SPROULL, New York University
MARJORY S. BLUMENTHAL, Executive Director
HERBERT S. LIN, Senior Scientist
ALAN S. INOUYE, Senior Program Officer
JON EISENBERG, Senior Program Officer
LYNETTE I. MILLETT, Program Officer
CYNTHIA PATTERSON, Program Officer
JANET BRISCOE, Administrative Officer
MARGARET HUYNH, Senior Project Assistant
SUZANNE OSSA, Senior Project Assistant
DAVID DRAKE, Project Assistant
DAVID PADGHAM, Research Assistant
BRANDYE WILLIAMS, Office Assistant
vi
Preface
Continued advances in information technologies are enabling a
growing number of physical devices to be imbued with comput-
ing and communications capabilities. Aircraft, cars, household
appliances, cellular telephones, and health monitoring devices all contain
microprocessors that are being linked with other information processing
devices. Such examples represent only the very beginning of what is
possible. As microprocessors continue to shrink, wireless radios are also
becoming more powerful and compact. As the cost of these and related
technologies continues to decrease, computing and communications tech-
nologies will be embedded into everyday objects of all kinds to allow
objects to sense and react to their changing environments. Networks
comprising thousands or millions of sensors could monitor the environ-
ment, the battlefield, or the factory floor; smart spaces containing hun-
dreds of smart surfaces and intelligent appliances could provide access to
computational resources.
Getting to this point will not be easy. Networks of embedded com-
puters pose a host of challenges qualitatively different from those faced
by more traditional computers or stand-alone embedded computers be-
cause they will be more tightly integrated with their physical environ-
ments, more autonomous, and more constrained in terms of space, power,
and other resources. They will also need to operate, communicate, and
adapt in real time, often unattended. Enabling such innovation will
require that a number of research challenges be overcome. How can large
numbers of embedded computing devices assemble themselves seam-
vii
viii PREFACE
lessly into an integrated network? How can their performance be guaran-
teed? How can social issues raised by the advent of more pervasive
information collection and processing—for example, concerns about pri-
vacy, robustness, and usability—be addressed?
CHARGE TO THE COMMITTEE
To improve understanding of these issues and help guide future re-
search endeavors, the Defense Advanced Research Projects Agency
(DARPA) and the National Institute of Standards and Technology (NIST)
asked the Computer Science and Telecommunications Board (CSTB) of
the National Research Council (NRC) to conduct a study of networked
systems of embedded computers (EmNets) that would examine the kinds
of systems that might be developed and deployed in the future and iden-
tify areas in need of greater investigation. This report identifies opportu-
nities for the use of EmNets, examines the ways EmNets differ from more
traditional systems, and delineates the research topics that need to be
addressed. The objective is to develop a research agenda that could guide
federal programs related to computing research and inform the research
community (in industry, universities, and government) about the chal-
lenging needs of this emerging research area. This report examines both
issues related to components of embedded computers—such as hardware
needs, operating systems, programming capabilities, and human inter-
faces—and systems-level issues resulting from the interconnection of
multiple embedded computers—system architectures, coordination, ad-
aptation, reliability, security, safety, interoperability, stability, and guar-
anteed performance. To that end, the committee attempted to answer
questions such as the following:
• What are networked systems of embedded computing systems?
How do networks of embedded computers differ from more traditional
computer networks? How do these differences affect research needs?
• What types of applications could arise from greater networking of
embedded systems? What are the general characteristics of different ap-
plications? What would be the benefits and capabilities of such systems?
• How can systems of interconnected embedded processors be more
easily designed, developed, and maintained? How can system reliability,
safety, operability, and maintainability be ensured in networked systems?
How do such considerations differ for embedded and more traditional
forms of computing?
• What kinds of advances are needed in enabling component tech-
nologies, such as hardware devices, operating systems, and communica-
tions networks, to make EmNets possible and more capable?
PREFACE ix
• What types of user interfaces are needed to allow users to interact
with and to program systems composed of large numbers of inter-
connected embedded systems? How do these requirements differ for
different kinds of users (experts, novices, system integrators)? What types
of “programming” will consumers be expected to perform?
• How can the stability and effectiveness of interconnected systems
of embedded computers be assured if individual components come from
a wide variety of developers and use a variety of hardware and software
platforms, some of which may run the latest versions of the software, and
others of which may be several generations behind?
COMMITTEE COMPOSITION AND PROCESS
To conduct the study, CSTB assembled a committee of 15 members
from industry and academia with expertise in areas of apparent impor-
tance to EmNets, such as computing devices, very-large-scale integrated
circuit technology, networking, wireless communications, embedded op-
erating systems, software safety, distributed computing, programming
languages, human-computer interfaces and usability, and computer sys-
tem security.1 Several committee members brought with them a familiar-
ity with federal research programs related to EmNet technologies and
provided invaluable insight into the challenges of organizing research
programs in this area. Several committee members changed their organi-
zational affiliation during the course of the study, attesting to the dy-
namic nature of this field. Indeed, because of growing commercial inter-
est in ubiquitous or pervasive computing technology, two of the original
committee members, Walter Davis from Motorola and Ajei Gopal from
IBM, were unable to continue their participation in the project.
The committee met six times between December 1999 and March 2001
to plan its course of action, solicit testimony from relevant experts, delib-
erate its findings, and draft its final report. It continued its work by
electronic communications into the spring of 2001. During the course of
the project, the committee heard from information technology researchers
in industry and universities and from directors of government agencies
involved in funding computing research (including research related to
EmNets).2 It also met with people involved in developing and deploying
EmNets to serve a range of missions, from controlling lighting and heat-
ing systems in office buildings and automating manufacturing lines, to
1See Appendix A for biographies of committee members.
2See Appendix B for a list of briefers to the committee.