Csaba A. Szabó

Motivations, design and business models of wireless community networks

In this paper we provide an integrated presentation of applications, technologies and business models for wireless community network together with design considerations and examples. An overview is given of the state-of-the-affairs of wireless community networks. Driving forces and stakeholders of the projects and the applications and services will be presented for some carefully selected cases. We suggest a design methodology and illustrate its application to an ongoing digital city project in Hungary. Relevant business models are also analyzed.

Measurements to assist access network design with fixed WiMAX in urban environment

WiMAX is a wireless MAN technology designed to diminish the broadband gap in rural areas and to provide the last mile solution. Besides, the WiMAX also ensures efficient access method in urban environment due to the good NLOS behavior of the OFDM transmission technology. On the other hand, network design with WiMAX in urban environment is a rather challenging task. Our work is focused on the examination of WiMAX transmissions in urban area. We performed preliminary laboratory tests and extensive field measurements; some of the results are presented in this paper. The measurements were influenced by several factors including the radio environment, device arrangement and configuration and also transmission protocols, among others. Our conclusion is that careful design is required and several parameters should be considered to ensure optimal solution in a given environment.

Design considerations for broadband community area networks

During the last few years, a number of community area networks (CAN) have been launched in North America and Europe. Contrary to other telecommunication infrastructures, these networks are sponsored and financed by local governments and operate according to business considerations and are based on business models that are different from a classical telecom operator, requiring therefore a tailored business and technological solution. Main CAN customer groups include (i) telcos and ISPs, (ii) business customers, (iii) public sector institutions and (iv) residential users. The two main product groups are fiber and wavelength products offered to wholesale customers and data, voice and video services offered to public sector institutions. Although the individual technologies to be deployed within these networks are no different from those used in the advanced telecommunications systems operated by public carriers, community networks can be more creative in using leading edge broadband core and access technologies and in providing advanced services. The main objective of the paper is to demonstrate that CANs, if properly designed, implemented and managed, represent a viable business model as well as the right technology basis for providing e-government services, in particular, and for contributing to the development of an e-society, in general. A preliminary design of a province network in Northern Italy has been carried out by the authors and serves as a case study for this article.

Motivations, technologies, and sustainability models of wireless municipal networks

In this article we provide an integrated presentation of applications, technologies, and business models for wireless municipal networks together with design considerations. We give an overview on the state of affairs in municipal networks, presenting the driving forces and stakeholders of these projects, the applications and services for some carefully selected cases, and the available wireless technologies and regulatory issues. Then we outline the design methodology to build wireless municipal networks, presenting a pilot municipal network in Hungary, and discuss the relevant sustainability and business models, which are analyzed and illustrated by summaries of case studies.

Design considerations on the CREATE-NET testbed

The CREATE-NET testbed is a long term project aiming at implementing a best state-of-the-art infrastructure able to link together research centers, both from academia and industrial bodies, in order to create a fruitful collaborative environment to help generating new ideas for advanced applications and services, developing new protocols, testing and integrating different vendor equipments. This testbed is aimed to be unique as it covers novel topics such as optical and wireless integration and WiMAX experimentation for offering broadband access to rural communities. In this paper we present both the technical design issues and a general outline of the implementation process.

Testbed of a Novel Media Streaming Architecture for Heterogeneous Wireless Environment

The paper presents the testbed of a novel network architecture which aims at providing streaming media services in a heterogeneous environment where the subscribers are roaming among different wired/wireless access networks including ADSL, WiFi, 2.5G and 3G cellular and WiMAX. The architecture provides seamless connectivity during roaming, with adapting the quality of the delivered media stream to the changes of the network characteristics and to the capabilities of a wide variety of devices. The paper presents general design considerations, focuses on a novel vertical handover mechanism, its implementation and evaluation in the testbed, as well as discusses media processing aspects. The different subsystems are currently being integrated into a single testbed which will provide an open environment for experimentation and will be suitable for technology transfer to network service providers and content providers.

Design considerations of a novel media streaming architecture for heterogeneous access environment

The paper reports on intermediate results of an ongoing R&D project which aims at designing, implementing and evaluating a novel network architecture in order to provide streaming media services in a heterogeneous environment where the subscribers are roaming across different wired/wireless access networks including ADSL, WiFi, 2.5G and 3G cellular and also, in the near future, WiMAX. In such a system, seamless connectivity has to be maintained during all phases of roaming, the quality of the delivered media stream has to be adjusted to the changes of the network characteristics and to the capabilities of a wide variety of devices, and adaptive charging for the content has to be integrated too. An overview of our proposed network architecture is given, its key components such as the methods of media handling on the server and client sides, capability matching considerations, security and payment techniques are outlined, with special emphasis on our NGN-conform, SIP-based vertical handover mechanism.

Business models and technologies for wireless community networks

Providing broadband access to citizens, communities, public institutions and developing businesses has become a strategic objective for governments and international organizations worldwide. In particular, serious problems related to the ldquodigital dividerdquo have been widely recognized by public administrations. However, the solution to these problems is not straightforward. Although the appropriate technologies are there, telecommunication companies cannot deploy them as the large costs and very long return of investment makes it prohibitive according to their usual business models.

Digital community ecosystems: Through a new and sustainable local DE development strategy

When studying Digital Ecosystems infrastructures we usually consider the peer-to-peer network and the other elements of the service-oriented infrastructure. This paper opens the discussion on DE infrastructures by considering DEs as regional broadband innovations that should both interact with other innovations, like Community Networks, and be recreated from participatory projects. We therefore overcome the definition of DE as technological substrate, adopting a socio-technical perspective on infrastructures that opens the discussion on how develop Digital Community Ecosystems.

Automatic Cartoon Colorization Based on Convolutional Neural Network

This paper deals with automatic cartoon colorization. This is a hard issue, since it is an ill-posed problem that usually requires user intervention to achieve high quality. Motivated by the recent successes in natural image colorization based on deep learning techniques, we investigate the colorization problem at the cartoon domain using Convolutional Neural Network. To our best knowledge, no existing papers or research studies address this problem using deep learning techniques. Here we investigate a deep Convolutional Neural Network based automatic color filling method for cartoons.