Associating Replication and Recovery Protocols for Replicated Databases ∗

Database replication consists in storage copies of the data in multiple sites for increasing availability and perfor-mance. However, it is necessary to maintain copies updated to ensure consistency. The recovery task basically consists in transferring the information lost during the failure inter-val, from one or more replicas that have been active to re-covering replicas, without altering the service capability. A good replication system must use simple technics, tol-erate work overload, keep consistency, provide operability and avoid transactions rollback [6]. In a similar way, a good recovery protocol must use simple technics, distribute in an efficient way the recovery work among available sites and allow the concurrency of ongoing transactions. The main goal of this work is to present a revision of the replication and recovery protocols developed in the las