Optimization of a DWDM Optical Fibre ICT System S.M.Pazi, C.R.Chatwin, R.C.Young, P.M.Birch, and W. Wang Industrial Informatics Research Group, Department of Engineering and Design School of Science and Technology, University of Sussex Falmer, Brighton BN1 9QT Phone: +44-1273-872642 Fax: +44-1273-678399 Abstract DWDM optical fibre networks have revolutionized long distance data transport and delivered high data transmission rates, low cost, extremely low bit error rate, and ICT operational simplification. In this paper, we report on an optical DWDM network concept that will provide ICT services to the majority of the people who live in the urban and rural areas of Tanzania at an affordable cost. This paper also analyses the system impairment effects for data transmission rates of 2.5 GB/s and 10 Gb/s per wavelength channel in a proposed optical DWDM network. The results show that a data rate of 2.5 Gb/s can be successfully transmitted over long distances with minimum system impairments, and achieves better system performance than with a rate of 10 Gb/s per wavelength channel. 1. INTRODUCTION Tanzania lags behind the rest of the world in the ICT sector, despite the ICT policy (2003) [1] that provided guidelines for the country to become a hub of ICT infrastructure and ICT solutions. Tanzania doesn’t have an internationally connected ICT infrastructure that provides ICT services to the majority of the people who live in the urban and rural areas. The connection to the rest of the world is still provided by expensive Satellite links. The majority of the people who live in rural areas do not have an Internet connection, and those who live in urban areas depend on expensive low speed satellite connections. For example, the monthly charge for a residential Internet bandwidth of 64 kbps is approximately $60 US [2]. In Tanzania, the penetration of satellite links is growing rapidly but still the majority of customers are in urban areas. Private and government organizations can’t afford to receive more Internet bandwidth because of the high cost of satellite connection, for example the cost to receive a commercial bandwidth of 512 kbps in Tanzania is approximately $9600 per annum [2]. Whilst, in other parts of the world the costs for the Internet access is decreasing, and also the speed and capacity are increasing due to the use of optical DWDM network technology. Therefore, for Tanzania to close the gap with other countries and enhance sustainable socio-economic development and accelerated poverty reduction both nationally and globally; there is a need to deploy ICT infrastructure using optical DWDM network technology. DWDM network is an optical fibre technology, which multiplexes many signals of different wavelengths