+44 (0)1509 263171
Please use this identifier to cite or link to this item:
|Title: ||Priority related QoS in TCP/IPv6 networks|
|Authors: ||Li, Yunqiu|
|Issue Date: ||2008|
|Publisher: ||© Yunqiu Li|
|Abstract: ||Active Queue Management (AQM) algorithms have been introduced for routers
supporting TCP dataflows to assist the TCP congestion control mechanism to perform
satisfactorily in all circumstances. However, today the Internet is expected to provide a
distinctly different service to different users based on the value and content accessed, etc.
The most popular AQM algorithm, Random Early Detection (RED), is famous for its
fairness-addressed characteristic, which makes Quality of Service (QoS) differentiation
impossible for it, and many other RED-based algorithms, while working on their own.
The introduction of the IPv6 header flow labelling ability will allow new AQM
algorithms which can provide differentiated levels of QoS based on user demands to be
This thesis aims to develop a methodology for the AQM algorithms to work in
conjunction with the IPv6 flow labelling ability, so as to provide acceptable Quality of
Service (QoS) according to the end users' dynamically varying QoS requirements. We
aim to offer a simple and generic process, which is adequately adoptable in Differentiated
Services (DiffServ) TCP/IPv6 environments. The contribution of this thesis is four-fold.
Firstly it develops a novel approach to allow AQM routers to track the QoS status of the
dataflow and provide a differentiated QoS according to user requirement. Secondly, an
AQM algorithm is developed from the classic Proportional Integral controller with the
ability to support different QoS requirements with a faster response time. Thirdly, we
have developed a mechanism to aid the AQM algorithm in predicting the queue length
and improving system performance. Finally, we have proposed schemes to provide
service differentiation for flows with different priorities in DiffServ Networks.
We demonstrate the proposed algorithms through simulations in Network Simulator
2 (NS2). The proposed methodologies are shown to exhibit many desirable properties,
such as providing differentiated throughputs and fast system response. Compared with
traditional AQM techniques, they offer significant improvements in guaranteeing
different levels of QoS in TCPIIPv6 networks according to user requirements and the
priority of the dataflows.|
|Description: ||A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.|
|Appears in Collections:||PhD Theses (Computer Science)|
Files associated with this item:
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.