
Accession Number : ADP002913
Title : Optimal File Allocation Problems for Distributed Data Bases in Unreliable Computer Networks II,
Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE LAB FOR INFORMATION AND DECISION SYSTEMS
Personal Author(s) : Ma,M. H. ; Athans,M.
Report Date : DEC 1983
Pagination or Media Count : 13
Abstract : The problem investigated consists of determining the optimal locations of files and the number of redundant copies of these files, in a vulnerable command, control and communications network. It is assumed that each node and link of the communications network can fail independently of the others. The optimization problem maximizes the probability that a commander is able to access the subset of the files that he needs while minimizing the networkwide costs. These networkwide costs are storage costs and costs due to the time delay in query and update requests of the distributed data base system. The problem can be shown to reduce to a zeroone liner programming problem. The authors look for theorems which reduce the complexity of the solution of the zeroone linear programs. Finally a heuristic algorithm has been developed to solve the zeroone linear program. An efficient polynomial time algorithm has been developed for the totally reliable network case. They try to extend the efficient polynomial time algorithm to the unreliable network case. (Author)
Descriptors : *Computer files, *Data bases, *Communications networks, *Computer communications, *Linear programming, Allocations, Reliability(Electronics), Position(Location), Optimization, Algorithms, Military commanders, Access, Delay
Distribution Statement : APPROVED FOR PUBLIC RELEASE