Abstract
The notion QoS (Quality of Services) has been proposed to capture the qualitatively or quantitatively defined performance contract between the service provider and the user applications. However, the diversity of notions of QoS is remarkable. For the researcher working in video coding, QoS is a subjective measure of channel quality, whereas others see QoS as a need for networks to provide performance bound, and still others see QoS in terms of network availability in the presence of failure. Therefore, the QoS requirements in different types of networks are varied. To provide the desired QoS requirements for a network, a resource management scheme should be devised specifically for such network. In this dissertation, we outline the QoS requirements and the resource management schemes for mobile and high-speed networks. For mobile networks, especially the Personal Communications Services (PCS) networks, the provision of a seamless handoff environment is the most critical QoS requirement in wireless networks. We proposed a new PCS backbone architecture which provides fast and seamless handoff service to PCS users. For economic consideration, we also proposed a less expensive design with sophisticate channel allocation algorithm. The later approach also provides fast handoff while its force termination probability is far less than that of the existent ones. For wired high-speed networks, since nodes are not subject to roaming, the QoS requirements are usually focused on bandwidth, end-to-end delay, delay jitter, packet loss rate, or a combination of these parameters. For optical Metropolitan Area Network (MAN), the DQDB network, which is standardized by IEEE 802 project, is the most notable one. The most concerned QoS requirements in DQDB are the fairness in bandwidth usage and access delay. We propose a simple mechanism, which is slightly modified from the IEEE 802.6 standard, and its performance is far better than the ones proposed in literature, including the standard. The Internet is interconnected by heterogeneous networks, which can be cell-based (i.e., ATM networks) or packet based (i.e., IP networks). Research in QoS provision for cell-based and packet-based networks are mainly focus on the scheduling algorithms (or scheduler) deployed in switching (or routing) nodes. The function of the scheduler is to schedule the transmission order of received packets according to their QoS requirements, which are usually the minimum bandwidth and delay bound. We propose a new scheduling algorithm for cell-based and packet-based networks. The complexity of our algorithm is only O(1) and its performance is competitive to the WFQ, the most famous and widely used scheduling algorithm with O(N) complexity.