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Localised Routing Algorithms in Communication Networks with Quality of Service Constraints. Performance Evaluation and Enhancement of New Localised Routing Approaches to Provide Quality of Service for Computer and Communication Networks.Mohammad, Abdulbaset H. T. January 2010 (has links)
The Quality of Service (QoS) is a profound concept which is gaining increasing attention in the Internet industry. Best-effort applications are now no longer acceptable in certain situations needing high bandwidth provisioning, low loss and streaming of multimedia applications. New emerging multimedia applications are requiring new levels of quality of services beyond those supported by best-effort networks. Quality of service routing is an essential part in any QoS architecture in communication networks. QoS routing aims to select a path among the many possible choices that has sufficient resources to accommodate the QoS requirements. QoS routing can significantly improve the network performance due to its awareness of the network QoS state. Most QoS routing algorithms require maintenance of the global network¿s state information to make routing decisions. Global state information needs to be periodically exchanged among routers since the efficiency of a routing algorithm depends on link-state information accuracy. However, most QoS routing algorithms suffer from scalability due to the high communication overhead and the high computation effort associated with maintaining accurate link state information and distributing global state information to each node in the network. The ultimate goal of this thesis is to contribute towards enhancing the scalability of QoS routing algorithms. Towards this goal, the thesis is focused on Localised QoS routing algorithms proposed to overcome the problems of using global network state information. Using such an approach, the source node makes routing decisions based on the local state information for each node in the path.
Localised QoS routing algorithms avoid the problems associated in the global network state, like high communication and processing overheads. In Localised QoS routing algorithms each source node maintains a predetermined set of candidate paths for each destination and avoids the problems associated with the
maintenance of a global network state by using locally collected flow statistics and flow blocking probabilities. / Libya's higher education
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Performance analysis and improvement of InfiniBand networks. Modelling and effective Quality-of-Service mechanisms for interconnection networks in cluster computing systems.Yan, Shihang January 2012 (has links)
The InfiniBand Architecture (IBA) network has been proposed as a new
industrial standard with high-bandwidth and low-latency suitable for constructing
high-performance interconnected cluster computing systems. This architecture
replaces the traditional bus-based interconnection with a switch-based network for
the server Input-Output (I/O) and inter-processor communications. The efficient
Quality-of-Service (QoS) mechanism is fundamental to ensure the import at QoS
metrics, such as maximum throughput and minimum latency, leaving aside other
aspects like guarantee to reduce the delay, blocking probability, and mean queue
length, etc.
Performance modelling and analysis has been and continues to be of great
theoretical and practical importance in the design and development of
communication networks. This thesis aims to investigate efficient and cost-effective
QoS mechanisms for performance analysis and improvement of InfiniBand
networks in cluster-based computing systems.
Firstly, a rate-based source-response link-by-link admission and congestion
control function with improved Explicit Congestion Notification (ECN) packet
marking scheme is developed. This function adopts the rate control to reduce
congestion of multiple-class traffic. Secondly, a credit-based flow control scheme is
presented to reduce the mean queue length, throughput and response time of the system. In order to evaluate the performance of this scheme, a new queueing
network model is developed. Theoretical analysis and simulation experiments show
that these two schemes are quite effective and suitable for InfiniBand networks.
Finally, to obtain a thorough and deep understanding of the performance attributes
of InfiniBand Architecture network, two efficient threshold function flow control
mechanisms are proposed to enhance the QoS of InfiniBand networks; one is Entry
Threshold that sets the threshold for each entry in the arbitration table, and other is
Arrival Job Threshold that sets the threshold based on the number of jobs in each
Virtual Lane. Furthermore, the principle of Maximum Entropy is adopted to analyse
these two new mechanisms with the Generalized Exponential (GE)-Type
distribution for modelling the inter-arrival times and service times of the input traffic.
Extensive simulation experiments are conducted to validate the accuracy of the
analytical models.
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Resource Allocation in Mobile and Wireless NetworksOwens, Harold, II 08 1900 (has links)
The resources (memory, power and bandwidth) are limited in wireless and mobile networks. Previous research has shown that the quality of service (QoS) of the mobile client can be improved through efficient resources management. This thesis contains two areas of research that are strongly interrelated. In the first area of research, we extended the MoSync Algorithm, a network application layer media synchronization algorithm, to allow play-out of multimedia packets by the base station upon the mobile client in a First-In-First-Out (FIFO), Highest-Priority-First (PQ), Weighted Fair-Queuing (WFQ) and Round-Robin (RR) order. In the second area of research, we make modifications to the DSR and TORA routing algorithms to make them energy aware routing protocols. Our research shows that the QoS of the mobile client can be drastically improved through effective resource allocation.
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Monitoring Remote Financial Transaction Control Devices Using SNMP Over TCPIqbal, Asif 02 April 2009 (has links)
No description available.
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A BANDWIDTH ALLOCATION FRAMEWORK USING TIME ADAPTABILITY FOR MULTIMEDIA TRAFFIC IN WIRELESS AND MOBILE CELLULAR NETWORKSCHANDA, PRITAM 27 September 2005 (has links)
No description available.
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RESOURCE ALLOCATION IN INTEGRATED WIRELESS AND MOBILE NETWORKSLI, WEI January 2005 (has links)
No description available.
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HANDOFF SCHEMES FOR THE IEEE 802.11 WIRELESS LANsCHINTALA, VENKATA MANOJ 02 July 2007 (has links)
No description available.
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PERFORMANCE ANALYSIS OF HYBRID RESERVATION HANDOFF SCHEME FOR INTEGRATED WIRELESS MOBILE NETWORKWANG, JINGAO 11 October 2001 (has links)
No description available.
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A PRIORITY-BASED RESOURCE MANAGEMENT APPROACH FOR DYNAMIC AND HARD MISSION CRITICAL REAL-TIME SYSTEMSShah, Purvi 21 April 2005 (has links)
No description available.
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Impact of QoS and contextual parameters on QoE in a videoconferencing applicationMadhi, Kristi January 2016 (has links)
This project will be based in an objective and as well as subjective study related to Quality of Experience in a video conference application, appear.in. Indeed the study puts emphasis on finding possible correlations between Quality of Service parameters, that in the study are represented by some of the most meaningful network parameters, and contextual parameters with Quality of Experience. To achieve this the study was based in two different scenarios using two test environments. One is based on having an all free test and the other conducted in a created test-bad for monitoring and altering network parameters to see how user respond to the changes. Both scenarios were accompanied by a survey that provided useful information about the subjective perception of different individuals that took part in the testing phase.The project is divided in two phases where we set up the required environments for the test and then we process results to find correlation between the above mentioned parameters.In the end of the project all the results and the conclusions are presented providing a clearer view for what was done. The project itself might represent a good foundation to be used in the future for other studies related to video conferencing application.
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