In search of simplicity: A Self-Organizing Group Communication Overlay 1 In Search of Simplicity: A Self-Organizing Group Communication Overlay

Abstract: Group communication primitives have broad utility as building blocks for distributed applications. The challenge is to create and maintain the distributed structures that support these primitives while accounting for volatile end-nodes and variable network characteristics. Most solutions proposed to date rely on complex algorithms or on global information, thus limiting the scale of deployments and acceptance outside the academic realm. This article introduces a low-complexity, self-organizing solution for building and maintaining data dissemination trees, that we refer to as UMO (Unstructured Multi-source Overlay). UMO uses traditional distributed systems techniques: layering, soft-state, and passive data collection to adapt to the dynamics of the physical network and maintain data dissemination trees. The result is a simple, adaptive system with lower overheads than more complex alternatives. We implemented UMO and evaluated it on a 100-node PlanetLab testbed and on up to 1024-node emulated ModelNet networks. Extensive experimental evaluations demonstrate UMO’s low overhead, efficient network usage compared to alternative solutions, and ability to quickly adapt to network changes and to recover from failures