The maintenance of common data in a distributed system

Abstract

A basic task in distributed computation is the maintenance at each processor of the network, of a current and accurate copy of a common database. A primary example is the maintenance, for routing and other purposes, of a record of the current topology of the system. Such a database must be updated in the wake of locally generated changes to its contents. Due to previous disconnections of parts of the network, a maintenance protocol may need to update processors holding widely varying versions of the database. We provide a deterministic protocol for this problem, which has only polylogarithmic overhead in its time and communication complexities. Previous deterministic solutions required polynomial overhead in at least one of these measures.