A flexible framework for replication in distributed systems

The goal of the work described in this paper was to build a flexible framework for different replication mechanisms in distributed systems that would be suitable for a wide variet, of users and applications. A framework was developed that supports multiple replication mechanisms, allows different objects to be maintained with different replication mechanisms, and enables application programmers to provide their own replication mechanisms. It will be argued that this framework allowed the needs of diverse users and applications in large distributed systems to be met. Our work has produced two significant contributions. First, after an examination of replication mechanisms used in distributed systems, a flexible framework that supports multiple replication mechanisms together was designed and developed. Second, following an examination of different levels of replication between replicas, a unified framework for them was produced. This multi-level replication allows the framework to work well with mobile computing by placing different replicas on mobile sites.