Consistent Data Replication: Is It Feasible in WANs?

Recent proposals have shown that database replication providing 1-copy-serializability can have excellent performance in LAN environments by using powerful multicast primitives. In this paper, we evaluate whether a similar approach is feasible in WAN environments. We identify the most crucial bottlenecks of the existing protocols, and propose optimizations that alleviate the identified problems. Our experiments show that performance remains acceptable even for medium sized systems, and data replication guaranteeing 1-copy-serializability is a serious alternative to weaker approaches in WAN environments.