In Service Oriented Architecture (SOA), web services may span several sites or logical tiers, each responsible for some part of the service. Most services need to be highly reliable and should allow no data corruption. A known problem in distributed systems that may lead to data corruption or inconsistency is the partition problem, also known as the split-brain phenomena. A split-brain occurs when a network, hardware, or software malfunction breaks a cluster Of Computer into several separate sub-clusters that reside side by side and are not aware of each other. When, during a session, two or more of these sub-clusters serve the same client, the data may become inconsistent or corrupted. ITRA - Inter Tier Relationship Architecture [1] enables web services to transparently recover from multiple failures in a multi-tier environment and to achieve continuous availability. However, the ITRA protocol does not handle partitions. In this paper we propose an extension to ITRA that supports continuous availability under partitions. Our unique approach, discussed in this paper, deals with partitions in multi-tier environments using the collaboration of neighboring tiers.
