Predictive Quality Of Service Schemes For Real-Time Multimedia Applications In Communications

Subramaniam, Shamala (1999) Predictive Quality Of Service Schemes For Real-Time Multimedia Applications In Communications. Masters thesis, Universiti Pertanian Malaysia.

[img] PDF
1298Kb

Abstract

In guaranteed QoS resources are reserved based on the worst-case analysis. This scheme guarantees QoS but results in low resource utilisation, subsequently depriving other users from acquiring service. In contrary, predictive QoS allocates an initial amount of resource, whereby QoS is guaranteed with a certain probability of degradation. This scheme is tailored for applications that are adaptive and robust towards sudden fluctuations in the service provided. The nature of multimedia data such as the variable bit rate has encouraged the implementation of predictive Quality of Service (QoS) as compared to guaranteed QoS. In a typical QoS scheme, two factors contribute to the computation of packet loss, which are : (i) a new packet dropped due to buffer overflow and (ii) a buffered packet dropped due to expired delay. The buffer resource is increased when the observed packet loss ratio has violated the requested level of packet loss ratio. The limitations in this scheme is caused by the admission of all packets into the buffer, inclusive of packets that will eventually be dropped due to expired delay. Subsequently, this results in poor resource management. In this research, two pro-active dynamic QoS control schemes are designed, the dynamic QoS control scheme with delay estimation, and the hybrid dynamic QoS control scheme. In both schemes, every new packet arrival is compared against the estimated delay it will experience, before being admitted into the buffer. If the estimated delay expires the requested delay bound, then the packet is dropped. In the hybrid scheme, every packet is checked before being admitted into the buffer, and also, the packets successfully admitted into the buffer are evaluated on the actual delay experienced before being transmitted to the receIver. The results obtained through the simulation models have shown that two schemes have significantly improved the average delay for different traffic patterns. In addition to improving the average delay in delay sensitive traffic, improvement is seen in the average packet loss ratio, and subsequently increasing the throughput for delay sensitive traffic. However, in packet loss sensitive traffic, the old scheme remains beneficial. The proposed scheme can be adopted for multimedia applications to enhance the QoS in terms of better delay and improved utilisation.

Item Type:Thesis (Masters)
Subject:Multimedia systems
Subject:Telecommunication systems
Subject:Multimedia communications
Chairman Supervisor:Associate Professor Ashwani Kumar Ramani, PhD
Call Number:FSKTM 1999 5
Faculty or Institute:Faculty of Computer Science and Information Technology
ID Code:11893
Deposited By: Mohd Nezeri Mohamad
Deposited On:19 Jul 2011 05:29
Last Modified:19 Jul 2011 05:29

Repository Staff Only: item control page

Document Download Statistics

This item has been downloaded for since 19 Jul 2011 05:29.

View statistics for "Predictive Quality Of Service Schemes For Real-Time Multimedia Applications In Communications "


Universiti Putra Malaysia Institutional Repository

Universiti Putra Malaysia Institutional Repository is an on-line digital archive that serves as a central collection and storage of scientific information and research at the Universiti Putra Malaysia.

Currently, the collections deposited in the IR consists of Master and PhD theses, Master and PhD Project Report, Journal Articles, Journal Bulletins, Conference Papers, UPM News, Newspaper Cuttings, Patents and Inaugural Lectures.

As the policy of the university does not permit users to view thesis in full text, access is only given to the first 24 pages only.