Support Quality Of Service Guarantees Research Articles

Bandwidth allocation based on priority and excess-bandwidth-utilized algorithm in WDM/TDM PON

WDM/TDM passive optical network (PON) is being viewed as a promising solution for delivering multiple services and applications, such as high-definition video, video conference and data traffic. This paper introduces a novel bandwidth allocation scheme to efficiently utilize the bandwidth and support QoS (Quality of Service) guarantees in WDM/TDM PON. We develop the priority-based transmission windows and investigate the fair bandwidth allocation by using linearly proportional algorithm. Specially, the proposed scheme can increase the bandwidth-utilized rate (BUR) by collecting and allocating the excess bandwidths from both light-loaded ONUs (time domain) and wavelength domain. Besides, the performance of delay-sensitive services is greatly improved without degrading QoS guarantees for other services due to our priority-based scheme. Finally, we conduct detailed simulation experiments to research the performance and demonstrate the effectiveness of the proposed scheme.

Quality-of-Service routing with path information aggregation

Most of the research proposals on Quality-of-Service (QoS) mechanisms have focused on providing guarantees in a single domain. Supporting QoS guarantees in the interdomain setting has been receiving more research attention recently. Most of the proposals for interdomain QoS routing has focused on a link-state protocol and/or a single QoS metric. Our proposal differs from the existing work in the literature in three major ways: (1) our approach is based on a distance-vector protocol, similar to BGP; the de facto interdomain routing protocol in the Internet, (2) we consider both bandwidth and delay simultaneously unlike the other studies which either considered one metric or made the decision on only one of metrics even when they disseminated more than one metric, and (3) we use a line segment to represent the domain level QoS information. To the best of our knowledge, our study is the first proposal in the literature that models the domains by a line segment for inter-domain QoS routing purposes under a distance-vector routing protocol to find a path that satisfy both bandwidth and delay requirements.

Design of a High-Performance IP Switching Architecture

In this study we present the architecture for use in high-performance switching networks with support quality of service (QoS) guarantees. Quality of services guarantees in terms of delay, through-put and loss rate can be provided by using mechanism's support like scheduling and buffer management at switching architecture in packet switching networks. Our architecture is based on a new data structure for the scheduling and memories management which is the circular linked list and the pipeline for the active queues elements. In addition to being very fast, the architecture also scales very well to a large number of priority levels and to large queue size. We give a detailed description of the block that support QoS guarantees. However our proposed architecture is composed of three parts: input controller, backplane and output controller. And we give the corresponding algorithms and the corresponding implementation of this architecture.

Dynamic-grouping bandwidth reservation scheme for multimedia wireless networks

In wireless networks carrying multimedia traffic (voice, video, data, and image), it becomes necessary to provide a quality-of-service(QoS) guarantee for multimedia traffic connections supported by the network. In order to provide mobile hosts with high QoS in the next-generation wireless networks, efficient and better bandwidth reservation schemes must be designed. This paper presents a novel dynamic-grouping bandwidth reservation scheme as a solution to support QoS guarantees in the next-generation wireless networks. The proposed scheme is based on the probabilistic resource estimation to provide QoS guarantees for multimedia traffic in wireless cellular networks. We establish several reservation time sections, called groups, according to the mobility information of mobile hosts of each base station. The amount of reserved bandwidth for each base station is dynamically adjusted for each reservation group. We use the dynamic-grouping bandwidth reservation scheme to reduce the connection blocking rate and connection dropping rate, while increasing the bandwidth utilization. The simulation results show that the dynamic-grouping bandwidth reservation scheme provides less connection-blocking rate and less connection-dropping rate and achieves high bandwidth utilization.