Since the early days of mankind the primary motivation for the establishment of communities has been the idea that by being part of an organized group the capabilities of an individual are improved. The great progress in the area of intercomputer communication led to the development of means by which stand-alone processing subsystems can be integrated into multicomputer communities. – Miron Livny, Study of Load Balancing Algorithms for Decentralized Distributed Processing Systems, . thesis, July 1983. Ready access to large amounts of computing power has been a persistent goal of computer scientists for decades | 11 Condor and the Grid Douglas Thain Todd Tannenbaum and Miron Livny University of Wisconsin-Madison Madison Wisconsin United States INTRODUCTION Since the early days of mankind the primary motivation for the establishment of communities has been the idea that by being part of an organized group the capabilities of an individual are improved. The great progress in the area of intercomputer communication led to the development of means by which stand-alone processing subsystems can be integrated into multicomputer communities. - Miron Livny Study of Load Balancing Algorithms for Decentralized Distributed Processing Systems . thesis July 1983. Ready access to large amounts of computing power has been a persistent goal of computer scientists for decades. Since the 1960s visions of computing utilities as pervasive and as simple as the telephone have motivated system designers 1 . It was recognized in the 1970s that such power could be achieved inexpensively with collections of small devices rather than expensive single supercomputers. Interest in schemes for managing distributed processors 2 3 4 became so popular that there was even once a minor controversy over the meaning of the word distributed 5 . Grid Computing - Making the Global Infrastructure a Reality. Edited by F. Berman A. Hey and G. Fox 2003 John Wiley Sons Ltd ISBN 0-470-85319-0 300 DOUGLAS THAIN TODD TANNENBAUM AND MIRON LIVNY As this early work made it clear that distributed computing was feasible theoretical researchers began to notice that distributed computing would be difficult. When messages may be lost corrupted or delayed precise algorithms must be used in order to build an understandable if not controllable system 6 7 8 9 . Such lessons were not lost on the system designers of the early 1980s. Production systems such as Locus 10 and Grapevine 11 recognized the fundamental tension between consistency and availability in the face of failures. In this environment the Condor project was .
