|
Abstract : |
Communication services that provide enhanced Quality of Service (QoS) guarantees related to dependability and real time are important for many applications in distributed systems. This paper presents real-time dependable (RTD) channels, a communication-oriented abstraction that can be configured to meet the QoS requirements of a variety of distributed applications. This customization ability is based on using CactusRT, a system that supports the construction of middleware services out of software modules called micro-protocols. Each micro-protocol implements a different semantic property or property variant, and interacts with other micro-protocols using an event-driven model supported by the CactusRT runtime system. In addition to RTD channels, CactusRT and its implementation are described. This prototype executes on a cluster of Pentium PCs running the OpenGroup/RI MK 7.3 Mach real-time operating system and CORDS, a system for building network protocols based on the x-kernel., |