MIT Reports to the President 1999–2000


LABORATORY FOR COMPUTER SCIENCE

The MIT Laboratory for Computer Science (LCS) is an interdepartmental laboratory whose principal goal is to create computer-communications technologies of high social utility with equal attention to forefront technological underpinnings and human utility.

Founded as Project MAC in 1963, the laboratory developed one of the world's earliest time-shared computer systems: the Compatible Time Sharing System (CTSS) and its successor, Multics, which laid the foundation for many of today’s systems and approaches, such as virtual memory, tree directories, on-line scheduling algorithms, line and page editors, secure operating systems, access control techniques, computer-aided design, and two of the earliest computer games, space wars and computer chess. Our partner in the Multics effort, AT&T, used many of the early ideas in their design of Unix.

These early developments laid the foundation for the laboratory’s work on knowledge based systems–the Macsyma program for symbolic mathematics–natural language understanding, and (with BBN) the development and use of packet networks in the Arpanet. In the late 1970s, Project MAC, renamed as the MIT Laboratory for Computer Science, embarked on research in clinical decision making, public cryptography, distributed systems and languages and parallel systems. These led to the RSA encryption algorithm, data abstractions which served as foundations of object oriented programming, the Clu and Argus distributed systems, the dataflow principle and associated languages and architectures of parallel systems (Monsoon, Id and StarT), local area networks, program specification and workstation development, where the laboratory contributed the earliest UNIX ports and compilers and the Nubus architecture. This research also led to the X Window System, a computer intercommunication and user interface system which was further developed by the laboratory’s X-Consortium and was widely used in over one thousand different software products. Since 1994, LCS has been the principal host of the World Wide Web Consortium of some 450 organizations that helps set the standard of a continuously evolving world wide web.

The laboratory’s current research falls into four principal categories: Information Infrastructure and Distributed Systems; Human-machine interaction; Science and Computer Science research; and Theory. The principal goals of these four categories are as follows:

In the areas of Information Infrastructure and Distributed Systems, we wish to understand principles and develop technologies for the architecture and use of highly scaleable information infrastructures that interconnect human-operated and autonomous computers. Transactions among such distributed systems involve the purchase, sale and free exchange of information and information work toward electronic commerce and shopping, health care, education, business, government and many other uses as well as increased automation of human work. We wish to explore new emerging forces such as collaboration across space and time and automation of computer-to-computer actions. We also expect this overall research to have a broad impact on future systems because virtually every machine will be connected to some information infrastructure and such infrastructures are expected to last for a very long time. The laboratory’s World Wide Web Consortium is a significant and major focus of our work in this area.

In the Human-Machine Interaction area, our technical goals are to understand and construct programs and machines that have greater and more useful sensory and cognitive capabilities so that they may communicate with one another and with people toward useful ends. The two principal areas of our focus are conversational spoken dialogue systems between people and machines and graphics systems used predominantly for output. In this area, we also strive to construct tomorrow’s servers by harnessing the power and economy of numerous processors working on the same task; relevant research spans parallel hardware and software architectures, that yield cost-performance improvements of several orders of magnitude relative to single processors.

In the Science and Computer-Science area, we are interested in exploring opportunities at the boundary of traditional science and information technology. Our research includes an extensive program of clinical decision systems research between medicine and computer science, and several research activities in biology and computer science.

Taken together, these three thrusts define the laboratory’s overarching goal: development, understanding and better human communication with tomorrow's information systems. In the laboratory’s fourth category of research, Theory, we strive to discover and understand the fundamental forces, rules, and limits of Information Science and Technology. As a result, theoretical work permeates our research efforts in the other three areas; for example, in the pursuit of parallel algorithms, fault tolerant computer networks, and privacy and authentication of communications. Theory also touches on the logic of programs, the inherent complexity of computations, and the use of cryptography and randomness in the formal characterization of knowledge. The laboratory expends a great deal of effort in theoretical computer science because its impact upon our world is expected to continue its past record of improving our understanding and helping us pursue new frontiers with new models, concepts, methods, and algorithms.

HIGHLIGHTS

Oxygen Launch

Oxygen is a new computer based on pervasive human-centered computing. It pulls together an abundance of technological resources toward creating a new breed of systems that cater to human—level needs, rather than machine-level details. This major research project was launched in September 1999, following funding by DARPA of a proposal for research to that end. Led by LCS, Oxygen is a collaborative effort with the Artificial Intelligence Laboratory and involves some 20 faculty and 150 researchers. Oxygen consists of eight new technologies: handheld units (Handy 21’s); stationary computers (Enviro 21’s), which are also connected to physical devices; a new network approach (Net21) that meets the needs of wireless mobility; (4) built-in speech understanding; individualized knowledge access; automation; collaboration; and customization. The first prototype of Oxygen should be ready two years hence. The project’s duration is five years. Oxygen is a broad project, an integrative effort that cuts across the Lab’s four principal categories of research. When it reaches full size, it is expected to occupy about one-third of LCS and AI Lab researchers. In May 2000, six companies (Acer, Delta, Hewlett Packard, Nokia, NTT and Philips) became partners to MIT in this effort, forming the Oxygen Alliance.

Network And Mobile Systems

Networks of the future will include a wide variety of mobile and wireless appliances and devices, in addition to general-purpose computers. The newly formed Networks and Mobile Systems group at LCS (http://nms.lcs.mit.edu/) co-led by Professors Hari Balakrishnan and John Guttag, is developing systems to enable a large class of pervasive computing applications for a world in which communication is ubiquitous and computation extends to network-enabled specialized devices (e.g., cameras, coffee machines, sensors, actuators, etc.). Realizing this vision is not easy because these environments are dynamic, network nodes are mobile, network performance fluctuates, and there is little known today about how to discover resources and services in this world.

The group’s approach to solving the problem of mobile resource discovery is a new naming system, called the Intentional Naming System (INS). In INS, names are "intentional," describing a sought resource by its properties (e.g., "find me the nearest, least-loaded color printer that can handle transparencies") rather than by its network location (as in "printer643.lcs.mit.edu" or "18.31.0.99"). Intentional naming provides flexibility and decentralized management, that allows applications to describe "what" they are looking for. Name resolvers in the network route requests to the appropriate locations by maintaining a dynamic mapping between service descriptions and network locations. This allows applications to self-organize because any data they need is obtained for them by INS based only on their descriptions, freeing them of the need to implement this machinery. A particularly interesting class of applications enabled by INS are "location-aware," meaning that they can change their behavior depending on the location of the user. To enable this, the group has designed an accurate location-support system called "Cricket," which uses a combination of radio-frequency and ultrasonic transmissions to allow mobile applications to discover and adapt to the location of resources, without compromising the privacy of mobile users.

Spoken Language Systems

This group has recently decided to offer open source license for their Galaxy Communicator architecture for conversational systems, so that institutions worldwide can adopt this standard without encumbrance. While the Group continues to conduct dialogue modeling research in order to support increasingly complex applications such as air travel planning, they also are starting to develop a set of tools that will enable developers and users to implement their own, simpler applications. These light systems, as they are called, will be particularly useful in the development of the Oxygen system.

World Wide Web Consortium

As of this report, 450 organizations have joined the consortium in order to participate in and contribute to the orderly evolution of the World Wide Web (W3). With three hosts and seven offices worldwide, the W3C is growing in influence, as offices succeed in promoting W3C work in specific regions. Key W3C technical developments include the growth of Extensible Markup Language (XML) and metadata efforts resulting in the W3C recommendation for Resource Description Framework (RDF). During this reporting period, Mr. Tim Berners Lee, director of the W3C, was named by Time Magazine as one of the twenty leading Scientists and Thinkers of the 20th Century. He was also awarded the 3Com Founders Chair, a newly established chair for LCS senior researchers. As the consortium size increases, it is facing, increasingly, the challenge of balancing a broad-based consensus for standards versus "driving" the Web forward based on technological capabilities and opportunities.

DISTINGUISHED LECTURE SERIES

The laboratory’s Distinguished Lecturer Series included presentations by Ruzena Bajcsy, Assistant Director, Directorate for CISE, NSF; Mahadev Stayanarayanan, Professor, Carnegie Mellon University; Vinton Cerf, Senior Vice President, MCI Telecommunications Corporation; and Ross Anderson, Professor, Cambridge University Computer Laboratory.

The laboratory is organized into 19 research groups, an administrative unit, and a computer service support unit. The laboratory’s membership comprises a total of 414 people, including 93 faculty and research staff, 190 graduate students, 46 undergraduate students, 52 visitors, affiliates, and postdoctoral associates and fellows, and 33 support staff. The academic affiliation of most of the laboratory’s faculty and students is with the Department of Electrical Engineering and Computer Science (EECS). About 38% of the laboratory’s funding comes from the US Government's Defense Advanced Research Projects Agency. The laboratory is also funded by and has extensive links with industrial organizations. These include partnerships for the construction of major systems such as the Oxygen Alliance, and consortia for the development of standards, such as the World Wide Web and the Oxygen Alliance.

More information about the laboratory can be found on the World Wide Web at http://www.lcs.mit.edu/.

Michael L. Dertouzos

MIT Reports to the President 1999–2000