Alleviating problems due to resource constraints in computer networks using additional information

Motivated and driven by the development of real-time multimedia applications, Quality of Service (QoS) has been a hot research area in computer networks for quite a long time. However, providing QoS in computer networks always faces network resource constraints: bandwidth, delay, and etc. Therefore, in this thesis, we try to alleviate these problems using additional information.;The objective of the online QoS routing problem is to minimize the call blocking probability due to insufficient network resources while supporting the required quality of service. A scheme is proposed to protect those critical links/paths that are crucial for future requests. In this problem, the network resource constraint is the limited network routing ability and the information we made use of is the co-relationship among the network paths/links which can reflect link criticality.;The second problem is the provisioning problem with enhanced Hose model in Virtual Private Networks (VPN). We enhanced the hose model specification to support delay requirements at the VPN endpoints. In this problem, the network resource constraint is the limited link bandwidth available for provisioning. We exploit the additional information of delay and the concept of tree diameter to alleviate the problem.;The third problem is the location management problem in Mobile Ad-hoc Networks (MANET). We proposed an integrated location management and location-aided routing system which uses location information as a guidance in QoS routing.