Scalable Multicast Platforms for a New Generation of Robust Distributed Applications

As distributed systems scale up and are deployed into increasingly sensitive settings, demand is rising for a new generation of communications middleware in support of application-level critical-computing uses. Ricochet, Tempest and Quicksilver are multicast-based systems developed to respond to this need. Ricochet and Quicksilver are multicast platforms; both are exceptionally scalable and support fault-tolerance properties that match closely with the needs of high-availability applications. Ricochet was designed to support time-critical applications replicated for scalability on data centers and clusters. These are typically coded in Java and run under Linux. Tempest is layered over Ricochet and automates most tasks of programming services for data centers. In contrast, Quicksilver focuses on high throughput and is targeted towards very large deployments of desktop computing systems, in support of publish-subscribe, event notification or media dissemination applications. In this paper we offer an overview of the systems and some of the new systems embeddings that, we believe, make them far easier to use than was the case in prior multicast platforms.