Edward A Lee: Modeling Heterogeneous Systems with Heterogeneous
Complex systems demand diversity in the modeling mechanisms. We see this
very clearly with cyber-physical systems (CPS), which combine computing
and networking with physical dynamics, and hence require model combinations
that integrate dynamics described using differential equations with
models of software. We also see it in applications where timed interactions
with components are combined with conventional algorithmic computations,
such as in networked computer games. We even see it in traditional software
systems when we have concurrent interactions between algorithmic components.
One way to deal with a diversity of requirements is to create very flexible
modeling frameworks that can be adapted to cover the field of interest.
The downside of this approach is a weakening of the semantics of the
frameworks that compromises interoperability, understandability, and
analyzability of the models. An alternative approach is to embrace
heterogeneity and to provide mechanisms for a diversity of models to
In this talk, I will describe an approach that achieves such interaction
between diverse models using a concept
that we call “abstract semantics.”
An abstract semantics is a deliberately incomplete semantics that cannot
by itself define a useful modeling framework. It instead focuses on
the interactions between diverse models, reducing the nature of those
interactions to a minimum that achieves a well-defined composition.
I will illustrate how such an abstract semantics can handle many
models that are built today (such as Statecharts, which combine state
machines with synchronous concurrent models, hybrid systems, which combine
state machines with differential equations, process networks, which combine
imperative programs with message passing concurrency, etc.). I will also
show how it handles combinations that are not readily available in modeling
tools today. I will illustrate these combinations with examples prototyped
in Ptolemy II.
Edward A. Lee is the Robert S. Pepper Distinguished Professor and
former chair of the Electrical Engineering and Computer Sciences
(EECS) department at U.C. Berkeley. His research interests center on
design, modeling, and simulation of embedded, real-time computational
systems. He is a director of Chess, the Berkeley Center for Hybrid and
Embedded Software Systems, and is the director of the Berkeley Ptolemy
project. He is co-author of five books and numerous papers. He has led
the development of several influential open-source software packages,
notably Ptolemy and its various spinoffs. His bachelors degree (B.S.)
is from Yale University (1979), his masters (S.M.) from MIT (1981),
and his Ph.D. from U.C. Berkeley (1986). From 1979 to 1982 he was a
member of technical staff at Bell Telephone Laboratories in Holmdel,
New Jersey, in the Advanced Data Communications Laboratory. He is a
co-founder of BDTI, Inc., where he is currently a Senior Technical
Advisor, and has consulted for a number of other companies. He is a
Fellow of the IEEE, was an NSF Presidential Young Investigator, and
won the 1997 Frederick Emmons Terman Award for Engineering Education.
Ole Lehrmann Madsen: A Unified Approach to Modeling and
Before the era of object-orientation, software development suffered
from the use of different languages and representation used for
analysis, design and implementation ― so-called structured
analysis and design (SA/SD). One of the strengths of
object-orientation is that it provided a unified approach for modeling
as well as for programming. This framework provided language
constructs as well as an associated conceptual framework.
The dual support for modeling and programming may be traced back to
SIMULA where one of the main goals was to provide a language for
modeling as well as programming. The focus on modeling and programming
has been one of the main characteristics of the Scandinavian School of
object-orientation where BETA is another representative.
Current mainstream of object-oriented software development, however,
seems to be going in the direction of separation of modeling and
programming. The numerous technologies and books on object-oriented
programming are primarily concerned with the technical aspects of
programming and pay very little attention to modeling aspects. On the
other side we see a development of modeling languages where the
emphasis is on graphical notations and executable models.
The purpose of this talk is to go back to the future and reintroduce
some of the ideas of SIMULA and discuss a unified approach to modeling
Ole Lehrmann Madsen is a professor of Computer Science, Aarhus
University, and director of the Alexandra Institute ltd. The Alexandra
Institute is a non-profit application-oriented research institute
information technology. The main goal of Alexandra is to bridge building
between research and private- and public organizations. Alexandra
organizes joint research projects based on problems in society
His area of research is object-oriented software systems, including
programming, modeling, languages, software development environments,
software architecture and pervasive computing. He was one of the
creators (together with Bent Bruun Kristensen, Birger Møller-Pedersen
and the late Kristen Nygaard) of the BETA programming language and the
Mjølner software development environment. He is a co-founder and
chairman of the board for Mjølner Informatics ltd, which is based on
BETA and the Mjølner project. He has a PhD. from Aarhus University in
computer science. He has previously been a research associate at CSLI
at Stanford University (1984-85) and senior research associate at Sun
Labs in Mountain View, California (1994-95).
Pamela Zave: Modeling the Internet
The Internet has changed the world. Its astounding success has led to
explosive growth in users, traffic, and applications, which has made
its original architecture and protocols obsolete. Currently the
networking community is questioning all aspects of Internet
technology, as researchers and stakeholders try to understand how to
meet new requirements for functionality, quality of service,
availability, and security.
In this technological crisis, one of our most powerful technical
tools, namely functional modeling (as opposed to performance
modeling), is being completely ignored. In this talk I explain how
modeling can be put to good use in the Internet context, how the
culture of the Internet Engineering Task Force and the networking
research community resist such efforts, and what might be done to
bring about a cultural change.
The talk will be illustrated with examples and results from several
projects using different modeling languages and techniques. These
The descriptions of these projects will emphasize topics such as the
search for the right modeling language and the search for principles
- A project to understand, formalize, and partially verify SIP, the
dominant protocol for IP-based multimedia applications. The official
specification of SIP consists of many thousands of pages of English
- A project revealing many unknown defects in the Chord routing
protocol, which is the most-cited protocol for maintenance of
- A project to generate modular telecommunication services from models
in a high-level, domain-specific language. This long-term project,
based on the DFC architecture, has already produced two large-scale
- A project to discover how to meet complex requirements for
application sessions using software composition.
Pamela Zave received an A.B. degree in English from Cornell
University, and a Ph.D. in computer sciences from the University of
Wisconsin-Madison. She has held positions at the University of
Maryland and Bell Labs, and is now with AT&T Laboratories-Research.
Dr. Zave is interested in all aspects of formal methods for software
engineering as applied to networks. For the past ten years she has
led a group of researchers building and analyzing IP-based voice and
multimedia services using the Distributed Feature Composition
architecture, invented by her and Michael A. Jackson.
Dr. Zave is an ACM Fellow and an AT&T Fellow. She has won two Most
Influential Paper awards, four Best Paper awards, the AT&T
Strategic Patent Award, and the AT&T Science and Technology
Medal. She is currently chair of IFIP Working Group 2.3 on Programming
Richard Soley: Ten Years of Model Driving
Dr. Richard Mark Soley is Chairman and Chief Executive Officer of the
Object Management Group, Inc. (OMG) and Executive Director of
the SOA Consortium.
As Chairman and CEO of the OMG, Dr. Soley is responsible for the
vision and direction of the world's largest consortium of its
type. Dr. Soley joined the nascent OMG as Technical Director in 1989,
leading the development of OMG's world-leading standardization process
and the original CORBA specification. In 1996, he led the effort to
move into vertical market standards (starting with healthcare,
finance, telecommunications and manufacturing) and modeling, leading
first to the Unified Modeling Language (UML) and later the Model
Driven Architecture (MDA). He also led the effort to establish the
SOA Consortium in January 2007.
Previously, Dr. Soley was a cofounder and former Chairman/CEO of
A I Architects, Inc, maker of the 386 HummingBoard and other PC and
workstation hardware and software. Prior to that, he consulted for
various technology companies and venture firms on matters pertaining
to software investment opportunities. Dr. Soley has also consulted for
IBM, Motorola, PictureTel, Texas Instruments, Gold Hill Computer and
others. He began his professional life at Honeywell Computer Systems
working on the Multics operating system.
A native of Baltimore, Maryland, U.S.A., Dr. Soley holds the
bachelor's, master's and doctoral degrees in Computer Science and
Engineering from the Massachusetts Institute of Technology.
Wednesday, 20-Oct-2010 14:38:25 CEST
- January 24, 2011
The conference proceedings are now available online as
- October 20, 2010
If you were unable to attend, the three
keynote presentations are now available.
- October 13, 2010
You can now admire the photographs
taken during the conference.