Video streaming over the Internet can be very difficult under the traditional client-server model. Peer-to-peer (P2P) systems, in which each participating peer contributes its upload bandwidth to other peers while it downloads data, have been successful in file-sharing applications, and they appear to be promising in delivering video contents, too. However, the existence of network address translation (NAT) is always considered as a challenge to peer-to-peer systems. NAT has been a practical solution to the Internet Protocol version 4 (IPv4) address exhaustion problem, as it reduces the usage of IP addresses by allowing multiple private hosts to share a single public IP address, but NAT can degrade the performance of a peer-to-peer system as it limits the direction of connectivity. Measurement studies show that a considerable fraction of peer-to-peer video streaming system users are behind NAT devices, and that their uplink bandwidth is not well utilized, but the literature lacks a quantitative analysis of the impact of NAT on the performance of P2P video streaming systems. In this thesis, an extensible analytical model is built to capture the performance for P2P live streaming systems with a certain percentage of users behind NAT and cannot be reached by NAT traversal techniques, the correctness of which is verified by software simulation. A simple mechanism is proposed in this thesis, which is able to effectively improve the system performance and fairness by counteracting the negative impact of NAT, and it can also be used to reduce the usage of server bandwidth. / Graduate
Identifer | oai:union.ndltd.org:uvic.ca/oai:dspace.library.uvic.ca:1828/3728 |
Date | 15 December 2011 |
Creators | Wei, Zhonghua |
Contributors | Pan, Jianping |
Source Sets | University of Victoria |
Language | English, English |
Detected Language | English |
Type | Thesis |
Rights | Available to the World Wide Web |
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