Ian H. White

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— An analysis of the sending rate of TCP control over Terabit per second rate links illustrates how future optical network characteristics, such as higher bitrates, network congestion, and larger data loads, would affect performance. We have implemented a model to allow increased sending rate for TCP. It is shown that even if the network bitrate is higher(More)
IPTV services are the fastest growing television services in the world today. This is a bandwidth intensive service, requiring low latency and tight control of jitter. To guarantee the quality of service required, service providers opt to multicast all TV channels at all times to everywhere. However, a significant number of channels are rarely watched, so(More)
— A testbed is described which allows both physical layer errors to be observed and analysed, as well as monitoring network performance via frame loss. Real network traffic loads can be used for testing, so that all measurements taken are representative of what would be seen in a deployed system. We illustrate our testbed with an examination of the(More)
One of the major concerns of IPTV network deployment is channel change delay (also known as zapping delay). This delay can add up to 2 s or more, and its main culprits are synchronisation and buffering of the media streams. Proving the importance of the problem is the already significant amount of literature addressing it. We start this paper with a survey(More)
— A physical layer coding scheme is designed to make optimal use of the available physical link, providing functionality to higher components in the network stack. This paper presents results of an exploration of the errors observed when an optical Gigabit Ethernet link is subject to attenuation. The results show that some data symbols suffer from a far(More)
One of the major concerns of IPTV network deployment is channel switching (or zapping) delay. This delay can add up to two seconds or more, and its main culprits are synchronisa-tion and buffering. By analysing an extensive dataset-comprising 255 thousand users, 150 TV channels, and covering a 6-month period-we have observed that most channel switching(More)
Today the energy consumption of Information and Communication Technology (ICT) industry is a significant contributor to the total energy demand in many developed countries. Recent studies show that the ICT industry is responsible for about 2% of the global emission of CO 2 and this percentage is predicted to increase as the Internet expands in bandwidth and(More)