An Autonomic Implementation of Reliable Broadcast Based on Dynamic Spanning Trees

Reliable broadcast is a basic building block of dependable distributed systems that allows the dissemination of messages to all processes guaranteeing that either none or all correct processes deliver the message, despite the occurrence of failures. In this work we introduce an autonomic strategy to implement reliable broadcast. Processes self-organize themselves on an overlay based on a hypercube-like topology. The overlay is maintained by the execution of an underlying monitoring algorithm that guarantees several logarithmic properties even in the presence of processes failures. The reliable broadcast strategy employs spanning trees that are dynamically built embedded in the overlay. Nodes fail by crashing, crashes are permanent, and the broadcast strategy works correctly for an arbitrary number of process crashes. After a process crashes, the reconstruction of the spanning trees is transparent, not inducing, therefore, performance degradation. Besides the formal specification, we also present experimental results obtained with simulation.