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This paper presents the work that is taking place in the Region of Western Greece in order to develop state-of-theart broadband infrastructure. The current status of broadband infrastructure in the region is being analyzed and the main principles on which the deployment of the networks will be based on is being described, by presenting the Metropolitan Area Networks and the Wireless access networks that will be developed. Two case studies of such municipal networks are also presented in this paper.Broadband infrastructure, fiber optics, municipal networks, wireless access netrwork

This paper describes functionality and architectural issues in the design of a web-based virtual community. This virtual community aims to meet the requirements of a virtual collaboration system with both autonomous and collaborative e-learning services, by supporting communities whose members interact and form groups based on their common interests.

SUMMARYThis paper proposes a mechanism for the congestion control for video transmission over Universal Mobile Telecommunications System (UMTS). Our scheme is applied when the mobile user experiences real time multimedia content and adopts the theory of a widely accepted rate control method in wired networks, namely equation-based rate control. In this approach, the transmission rate of the multimedia data is determined as a function of the packet loss rate, the round trip time and the packet size and the server explicitly adjusts its sending rate as a function of these parameters. Through a number of simulations and experiments we validate the correctness and measure the performance and efficiency of the mechanism. A first level of evaluation is carried out using the ns-2 simulator. A second level then validates the proposed mechanism in real world traffic scenarios by performing experiments in a commercial UMTS network.

The scheme of real time streaming video is one of the newcomers in wireless data communication, raising a number of new requirements in both telecommunication and data communication systems. This scheme applies when the user is experiencing real time multimedia content. This paper has as main target to study the performance of video transmission over the third generation cellular networks. In particular, we examine the performance of UMTS Dedicated Channels (DCHs) for real time MPEG-4 video transmission in Downlink direction. Finally, we examine if real time video transmission in conjunction with Internet traffic is applicable in UMTS radio interface.