Total Order Broadcast Protocols Research Articles

Time hybrid total order broadcast: Exploiting the inherent synchrony of broadcast networks

Total order broadcast is a fundamental communication primitive for the construction of highly-available systems. Informally, the primitive guarantees that messages sent by a group of processes are delivered to all processes in the same order. This paper investigates the design and performance of a very simple synchronous total order broadcast that is built atop of an asynchronous distributed system based on a broadcast network. Our Time Hybrid Total Order Broadcast (THyTOB) explores the inherent synchrony of the broadcast network to build a total order for the messages, while ensuring safety under asynchrony and in the presence of process failures. We assess the performance of THyTOB in an Ethernet-based commodity cluster, and show that it is on a par with the performance of other well-known, and more complex total order broadcast protocols inherently designed for the asynchronous model.

Throughput optimal total order broadcast for cluster environments

Total order broadcast is a fundamental communication primitive that plays a central role in bringing cheap software-based high availability to a wide range of services. This article studies the practical performance of such a primitive on a cluster of homogeneous machines. We present LCR, the first throughput optimal uniform total order broadcast protocol. LCR is based on a ring topology. It only relies on point-to-point inter-process communication and has a linear latency with respect to the number of processes. LCR is also fair in the sense that each process has an equal opportunity of having its messages delivered by all processes. We benchmark a C implementation of LCR against Spread and JGroups, two of the most widely used group communication packages. LCR provides higher throughput than the alternatives, over a large number of scenarios.

Open consensus

AbstractThis paper presents the abstraction of open consensus and argues for its use as an effective component for building reliable agreement protocols in practical asynchronous systems where processes and links can crash and recover. The specification of open consensus has a decoupled, on‐demand and re‐entrant flavour that make its use very efficient, especially in terms of forced logs, which are known to be major sources of overhead in distributed systems. We illustrate the use of open consensus as a basic building block to develop a modular, yet efficient, total‐order broadcast protocol. Finally, we describe our Java implementation of our open‐consensus abstraction and we convey our efficiency claims through some practical performance measures. Copyright © 2001 John Wiley & Sons, Ltd.