Communication Software for QoS Control in Distributed Real-Time Environments

There has been an increasing need of highly predictable, timely, and dependable communication services with QoS guarantees on an end-to-end basis either for embedded real-time applications or for multimedia-integrated distributed control. Performance objectives used in conventional networks -- such as maximizing the throughput, minimizing the response time, or providing fairness to users -- are not of the most important concern for both types of applications. Instead, resources, i.e., CPUs and I/O on end systems and bandwidth, buffer space and network adapters in the network should be appropriately reserved and managed to support multi-dimensional quality of service (QoS), i.e., high assurance, bounded delay, bounded delay jitter, distinction among messages of different levels of criticality, fault tolerance, and service availability, on an end-to-end basis, as well as application-specific tradeoffs among them.

The goal of the proposed research is thus to develop and demonstrate an environment -- an integrated set of network resource management techniques, middleware layers, and network software -- for supporting multi-dimensional QoS on an end-to-end basis and exporting a unified, well-defined API for distributed real-time environments.

Specifically, we consider in this project the following innovative research components:

Unified framework for achieving multi-dimensional QoS

Building of a network simulation tool based on the QoS framework

Software implementation and experimentation

Laboratory testbed for technology demonstration