Page type: faculty

Fred B. Schneider;Fred B. Schneider;Professor;PhD State Univ. of N.Y., Stony Brook, 1978;Techniques for understanding concurrent programs are becoming increasingly;important as distributed computing systems become widespread in;mission-critical applications. My research has focused on the development;of these techniques.;I have been heavily involved in applying assertional reasoning to the;design of concurrent, distributed, fault-tolerant, and real-time programs.;I am completing a textbook on this subject. Along with David Gries, I;continue investigations concerning our first-order equational logic E.;This past year, we streamlined the inference rules and evaluated a number;of techniques for handling undefined terms and partial functions.;Thomas Bressoud and I completed building and analyzing our hypervisor-based;implementation of replication management for HP's PA-RISC architecture.;Our protocols ensure that the sequence of instructions executed by two;virtual machines running on different physical processors are identical.;The protocols also coordinate I/O issued by these virtual machines. Use of;a hypervisor to implement replica coordination is attractive - at least, in;theory. When replica coordination is implemented in a hypervisor, it;instantly becomes available to all hardware realizations of the given;instruction-set architecture, including realizations that did not exist;when the hypervisor was written. Second, when replica coordination is;implemented in a hypervisor, a single implementation suffices for every;operating system that executes on that instruction-set architecture.;Finally, by implementing replica coordination in a hypervisor, the;applications programmer is freed from this task.;Jointly with Dag Johansen (University of Tromsø, Norway) and Robbert van;Renesse, I started the TACOMA project (Tromsø And COrnell Moving Agents) to;investigate support and use of mobile processes in building;mission-critical applications. By structuring a system in terms of agents,;applications can be constructed in which communication-network bandwidth is;conserved. Data may be accessed only by an agent executing at the same;site as the data resides. An agent typically will filter or otherwise;reduce the data it reads, carrying with it only the relevant information as;it roams the network. Two TACOMA prototypes have been completed, and we;are implementing a third system based on our experiences.;Finally, I developed with Scott Stoller a new algorithm for detecting;whether a particular computation of an asynchronous distributed system;could have passed through a global state satisfying some given state;predicate. The new algorithm allows more efficient detection than is;possible with previous algorithms.;University Activities;Sabbatical leave, 1994-95;Professional Activities;Editor-in-chief, Distributed Computing;Editor, Information Processing Letters;Editor, IEEE Transactions on Software Engineering;Editor, High Integrity Systems;Editor, Annals of Software Engineering;Editor, ACM Computing Surveys;Co-Editor, Texts and Monographs in Computer Science, Springer-Verlag;Program Committee Member, 3rd International School and Symposium on; Formal Techniques in Real-Time and Fault-Tolerant Systems;Program Committee Member, 3rd International Conference on the Mathematics; of Program Construction;Program Committee Member, 4th International Workshop On Responsive; Computer Systems;Program Committee Member, Workshop on Composability of Fault-resilient; Real-Time Systems;Program Committee Member, Fifth IFIP Working Conference on Dependable; Computing for Critical Applications;Program Committee Member, Sixteenth IEEE International Real-Time Systems; Symposium;Program Committee Member, DIMACS Workshop on Verification and Control; of Hybrid Systems;Steering committee, Center for High Integrity Software Systems; Assurance (CHISSA), National Institute of Standards and Technology;Member, ISAT Defensive Information Warfare Study Group, Advanced Research; Projects Agency;Review committee, Leibniz Center at Hebrew University;Member, IFIP Working Group 2.3 (Programming Methodology);Awards;Fellow, American Association for Advancement of Science;Fellow, Association for Computing Machinery;Lectures;Proof outlines for programs. 6 lectures. 15th International Summer; School, Marktoberdorf, Germany, July 1994.;On the origin of traditions. Banquet speech. 15th International Summer; School, Marktoberdorf, Germany, July 1994.;Reasoning about programs by exploiting the environment. AFOSR; Grantees/Contractors Meeting In Software and Systems, Washington,; D.C., Sept. 1994.;Verifying hybrid systems by exploiting the environment. Symposium on; Formal Techniques in Real-Time and Fault-Tolerant Systems.; Lubeck, Germany, Sept. 1994.;Panelist: comparative merits of synchronous, partially synchronous,; and asynchronous models for safety-critical real-time systems.; Symposium on Formal Techniques in Real-Time and Fault-Tolerant; Systems. Lubeck, Germany, Sept. 1994.;Moderator: issues in writing formal specifications. Specification and; Refinement of Reactive Systems. International Conference and Research; Center for Computer Science, Dagstuhl, Germany, Sept. 1994.;Merging policies. Workshop on Computer Support for Policy Analysis and; Design. George Mason University, Virginia, Dec. 1994.;Avoiding AAS mistakes. Invited speaker. Air Traffic Management Workshop,; NASA Ames Research Center, Feb. 1995.;Reasoning about programs by exploiting the environment. Technical; University of Munich. Munich, Germany, Feb. 1995.;Proof outlines of the past. University of North Carolina, Chapel Hill,; North Carolina, March 1995.;Adding fault-tolerance, virtually. Distinguished Lecture Series,; University of North Carolina, Chapel Hill, North Carolina, March 1995.;Moderator and panel organizer: teaching logic as tool. SIGCSE Technical; Symposium on Computer Science Education, Nashville, Tennessee, March 1995.;Proof outlines of the past. Technion, Haifa, Israel, March 1995.;Adding fault-tolerance, virtually. University of Tromsø, Tromsø, Norway,; April 1995.;Concurrent programs from specifications. University of Tromsø, Tromsø,; Norway, April 1995.;Placing agents on airplanes - a view of AAS and its successor. ARPA ISAT; Defensive Information Warfare Study Group Meeting, Washington, D.C.,; June 1995.;Publications;Reasoning about programs by exploiting the environment. Proceedings 21st; International Colloquium, ICALP'94 (Jerusalem, Israel, July 1994),; Lecture Notes in Computer Science 820, Springer-Verlag, New York,; 328-339 (with L. Fix).;Notes on proof outline logic. Working Material. 15th International Summer; School, Marktoberdorf, Germany, July 1994.;Research on fault-tolerant and real-time computing. Software and Systems; Program Summary. (Bolling Air Force Base, Washington D.C., Sept.; 1994), Air Force Office of Scientific Research, 75-77.;Hybrid verification by exploiting the environment. Formal Techniques in; Real-Time and Fault-Tolerant Systems (Lubeck, Germany, September; 1994), Lecture Notes in Computer Science, Volume 863, Springer-Verlag,; New York, 1-18 (with Limor Fix).;Equational propositional logic. Information Processing Letters 53, 3; (February 1995), 145-152 (with D. Gries).;Refinement for fault-tolerance: An aircraft hand-off protocol.; Foundations of Ultradependable Parallel and Distributed Computing,; Paradigms for Dependable Applications, Kluwer Academic Publishers,; 1994, 39-54 (with K. Marzullo and J. Dehn).;Teaching logic as a tool. Proceedings 26th SIGCSE Technical Symposium; on Computer Science Education (Nashville, Tennessee, March 1995),; SIGCSE Bulletin 27, 1, 384-385 (with D. Gries).;Operating system support for mobile agents. Proceedings Fifth Workshop on; Hot Topics in Operating Systems HOTOS-V (Orcas Island, Washington,; May 1995), 42-45 (with Dag Johansen and Robbert van Renesse).;Verifying programs that use causally-ordered message-passing. Science of; Computer Programming 24, 2 (1995), 105-128 (with S. Stoller).;On teaching proof. Arts & Sciences NewsLetter 16, 2 (Spring 1995), 3; (with D. Gries).;A new approach to discrete teaching mathematics. Primus V, 2 (June 1995),; 113-138 (with D. Gries).;Return to:;; 1994-1995 Annual Report Home Page;; Departmental Home Page;If you have questions or comments please contact:;www@cs.cornell.edu.;Last modified: 24 November 1995 by Denise Moore;(denise@cs.cornell.edu).;