Quality of Service (QoS) provisioning is an important challenge for future packet networks. There are many different aspects of Network QoS requirements such as performance, availability, reliability, security, etc. This thesis focuses on three performance-oriented problems among many problems. First, we look at a key theoretical problem for the multi-service Internet: an important technique, inter-class statistical resource sharing. We have developed a new approach for admission control in multi-class link-sharing environments that yields exact delay distributions and applies to a broad class of schedulers, including strict priority, earliest deadline first, and weighted fair queueing. These results represent a significant advance over traditional “isolation models” of multi-class networks. Second, we have developed a scalable technique for quality-of-service management for the Internet guaranteed real-time service, termed egress admission control. The approach achieves a service suitable for voice, real-time multimedia flows for example, yet without per-flow management required by the IETF's IntServ standard. Finally, we devise a packet-base multi-path scheduler. In networks, routes change over long-time scales whereas path characteristics change over short-time scales. We have integrated two traditionally separate concepts of routing and scheduling and develop an “opportunistic” multi-path scheduler that minimizes mean delay by exploiting short-time scale path information, while still satisfying routing objective over long-time scale.
展开▼
