Date Added: Jan 2011
Replication is the technique of using multiple copies of a server or a resource for better availability and performance. Each copy is called a replica. The main goal of replication is to improve availability, since a service is available even if some of its replicas are not. This helps mission critical services, such as many financial systems or reservation systems, where even a short outage can be very disruptive and expensive. A prerequisite for realizing the benefits of replication, however, is the development of high performance concurrency mechanism. Current applications, such as Web-based services, electronic commerce, mobile telecommunication system, etc., are distributed in nature and manipulate time-critical databases.