Quality Of Service Granularity Research Articles

Provisioning of QoS adaptability in wired-wireless integrated networks

The increasing number of mobile users and the popularity of real-time applications make wired-wireless integrated network extremely attractive. In this case, quality of service (QoS) adaptability is particularly important since some important features of the integrated network call for QoS adaptability, such as mobility, bursty applications and so on. Traditional QoS schemes include integrated service (IntServ) and differentiated service (DiffSev) as well as their variants. However, they are not able to balance well between scalability and QoS granularity. For example, IntServ faces the scalability problem, while DiffServ can only provide coarse granular QoS. In addition, they are also unable to efficiently support QoS adaptability. Therefore, a per-packet differentiated queueing service (DQS) was proposed. DQS was originally proposed to balance between scalability and QoS granularity in wired networks and then extended to wireless networks. This paper mainly discusses how to use DQS to support QoS adaptability in wired-wireless integrated networks. To this end, we propose a scheme to determine dynamic delay bounds, which is the key step to implement DQS to support QoS adaptability. Simulation studies along with some discussions are further conducted to investigate the QoS adaptability of the proposed scheme, especially in terms of its support of QoS adaptability to mobility and to bursty real-time applications.

Enhancing quality of service provisioning in wireless ad hoc networks using service vector paradigm

AbstractEmerging real‐time communications and multimedia applications necessitate the provisioning of Quality of Service (QoS) in Internet. Recently, a new concept, referred to as service vector, has been introduced to enhance the end‐to‐end QoS granularity, and at the same time, maintain the simplicity and scalability feature of the current differentiated services (DiffServ) networks. This work extends this concept to wireless ad hoc networks and proposes a cross‐layer architecture based on the combination of delay‐bounded wireless link level scheduling and the network layer service vector concept, resulting in significant power savings and finer end‐to‐end QoS granularity. The impact of various traffic arrival distributions and flows with different QoS requirements on the performance of this cross‐layer architecture is also investigated and evaluated. Copyright © 2006 John Wiley & Sons, Ltd.

Scalability and QoS guarantee for streams with (m,k)-firm deadline

Real-time media streams with (m,k)-firm are increasing and attractive as it proposes an alternative quality of service (QoS). In order to meet these ever increasing demands, the problem of scalability should be considered under limited resource. The problem is ignored in the existing solutions all along, because these solutions maintain a separate queue for each stream and per-stream state information. In this paper, we extend the work made in[Ji Ming Chen, Zhi Wang, Ye Qiong Song, and You Xian Sun. A scalable approach for streams with (m,k)-firm deadline. In Proceedings of IEEE Workshop on Quality of Service for Application Servers (2004 October)] and propose loss-rate balance (static) and stream number balance (dynamic) Class Selection Algorithm (CSA) for real-time media streams with (m,k)-firm, which is scalable while offering dynamic performance close to that of existing solutions. The effectiveness of static CSA (S-CSA) that captures the trade-off between scalability and QoS granularity is evaluated through extensive simulation studies. It is also shown that the S-CSA is as effective to guarantee QoS in terms of dynamic failure rate as the dynamic one.

A flexible and distributed architecture for adaptive end-to-end QoS provisioning in next-generation networks

A novel distributed end-to-end quality-of-service (QoS) provisioning architecture based on the concept of decoupling the end-to-end QoS provisioning from the service provisioning at routers in the differentiated service (DiffServ) network is proposed. The main objective of this architecture is to enhance the QoS granularity and flexibility offered in the DiffServ network model and improve both the network resource utilization and user benefits. The proposed architecture consists of a new endpoint admission control referred to as explicit endpoint admission control at the user side, the service vector which allows a data flow to choose different services at different routers along its data path, and a packet marking architecture and algorithm at the router side. The achievable performance of the proposed approach is studied, and the corresponding results demonstrate that the proposed mechanism can have better service differentiation capability and lower request dropping probability than the integrated service over DiffServ schemes. Furthermore, it is shown that it preserves a friendly networking environment for conventional transmission control protocol flows and maintains the simplicity feature of the DiffServ network model.

Dynamic class-based queue management for scalable media servers

Real-time media servers are becoming increasingly important due to the rapid transition of the Internet from text- and graphics-based applications to multimedia-driven environments. In order to meet these ever increasing demands, real-time media servers are responsible for supporting a large number of clients with a heterogeneous mix of quality of service (QoS) requirements. In this paper, we propose a dynamic class-based queue management scheme that effectively captures the trade-off between scalability and QoS granularity in a media server. We examine the adaptiveness of the scheme and its integration with the existing schedulers. Finally, we evaluate the effectiveness of the proposed scheme through extensive simulation studies.