A Scheme for Reliable Real-Time Messaging with Bounded Delays

Network-based real-time computing applications which require tightly bounded end-to-end delays have been increasing at a steady rate in recent years. A messaging layer that yields tight bounds on the latencies in detecting message losses and enables the application layer to initiate a timely recovery action has thus become highly desirable. In this paper we present a new reliable real-time messaging scheme called the Delay-Bounded Reliable Messaging Scheme (DB-RMS) that is aimed at meeting such requirements. It is built on top of the UDP sub-layer. DB-RMS provides multiple service options, each with different fault detection/recovery capabilities and different costs in terms of the execution overhead. This feature makes DB-RMS suitable for a variety of applications. The service options and the corresponding support protocols are presented first, followed by a formal analysis on the detection and reaction latency bounds under various service options. A messaging layer prototype using DB-RMS has been implemented. Performance measurements of the prototype implementation have been taken and the positive results obtained are also presented.