Broadcast with partial knowledge (preliminary version)

This work concerns the problem of broadcasting a large message efficiently when each processor has partial prior knowledge about the contents of the broadcast message. The partial information held by the processors might be out of date or otherwise erroneous, and consequently, different processors may hold conflict ing information. Tight bounds are “Dept. of Mathematics and Lab. for Computer Science, M. I. T., Cambridge, MA 02139. Supported by Air Force Contract TNDGAFOSR-860078, ARO contract DAAL03-86-K-0171, NSF contract CCR861 1442, and a special grant from IBM. tIBM T*J. Watson Research center, p-o. Box 704, Yorktown Heights, NY 10598, and Faculty of Electrical Engineering, The Technion, Haifa 32000, Israel. fIBM T.J. Watson Research center p,o. Box 704, Yorktown Heights, NY 10598. ~Aiken Computation Laboratory, Harvard University, Cambridge, MA 02138. Partially supported by ONR NOO014-85-K-0445. WDepartment of Applied Mathematics and Computer Science, The Weizmann Institute, Rehovot 76100, Israel. Supported in part by an Allen Fellowship, by a Walter and Elise Haaa Career Development Award and by a Bantrell Fellowship. Permission to copy without fee all or part of this material k granted provided that the copiesare not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to republish, requires a fee and/or specific permission. 01991 ACM 0-89791-439-2/91/0007/0153 $1.50 established for broadcast under such conditions, and applications of the broadcast protocol to other distributed computing problems are discussed.