A dissertation submitted in fulfilment of the requirements for the degree of Master of Science (Computer Science) Department of Computer Science, Faculty of Science and Agriculture, University of Zuluand, 2007. / With the rapid development of new applications, comes the drive to modify the current Internet to accommodate real-time multimedia applications. The current Internet uses a single queue per output port to buffer packets destined for that port. This often causes congestion leading to packet loss and delay. Real-time applications are delay and Joss sensitive. Therefore, there is a need to develop a buffer management system that will effectively accommodate both real-time and non-real-time applications.
In an attempt to efficiently allocate and manage output buffers of a router in the fixture Internet, in this research we have developed a buffer management scheme known as Dynamic Threshold Buffer Allocation Scheme (DTBAS). This scheme uses complete sharing with virtual partitioning. Pre-emption (i.e. removal of queued packets) is used to minimise congestion of high priority packets. Dynamic thresholds are used to determine the start and end of pre-emption. To further alleviate the congestion of high priority (real-time) packets, high priority OUT-packets are randomly dropped during the pre-emption period. To add some fairness to the scheme, low priority (non-real-time) packets are assigned a minimum buffer volume.
Simulation was conducted to evaluate the performance of the proposed scheme. The scheme was also compared with the Complete Sharing and Complete Partitioning schemes. It was found that DTBAS had the lowest average packet loss rate for real-time applications compared to other schemes. It was also found that DTBAS efficiently utilises its buffer space.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uzulu/oai:uzspace.unizulu.ac.za:10530/157 |
| Date | January 2007 |
| Creators | Pillai, Divya Balakrishna |
| Contributors | Xulu, S.S., Ojong, G.E. |
| Publisher | University of Zululand |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | application/pdf |
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