A crescente digitalização das mídias, disponibilidade de banda larga e convergência tecnológica possibilitam o surgimento de novos serviços, como o IPTV (Internet Protocol TeleVision), que visa disponibilizar serviços de televisão via TCP/IP sobre uma rede de banda larga privativa. Sem os devidos cuidados, entidades ou indivíduos monitorando o tráfego deste serviço passam a ter uma maior quantidade de informações sobre os indivíduos que os utilizam, muitas vezes violando a privacidade dos mesmos em um ambiente no qual tradicionalmente não há esta preocupação, como a sala de estar ou outro ambiente doméstico. O objetivo deste trabalho é propor uma arquitetura de IPTV que apresente mecanismos capazes de garantir um nível de privacidade maior do que o existente em sistemas de IPTV tradicionais, de maneira a inviabilizar para um observador o correlacionamento entre um usuário do serviço e os conteúdos por ele assistidos. / The increase in media digitalization, broadband availability and technological convergence, allows new services, such as the IPTV (Internet Protocol Television) service, which offers television-related services over a private broadband TCP/IP network. Without proper care, entities or individuals monitoring these services traffic obtain a large amount of information on the service users, and could violate their privacies in an environment in which traditionally there is no such preoccupation, like in a living-room or another domestic environment. The goal of this work is to propose an IPTV architecture capable of guaranteeing a higher privacy level than the existing in traditional IPTV systems, so that it is not viable for an observer to correlate a service user with the content he/she watches.

A crescente digitalização das mídias, disponibilidade de banda larga e convergência tecnológica possibilitam o surgimento de novos serviços, como o IPTV (Internet Protocol TeleVision), que visa disponibilizar serviços de televisão via TCP/IP sobre uma rede de banda larga privativa. Sem os devidos cuidados, entidades ou indivíduos monitorando o tráfego deste serviço passam a ter uma maior quantidade de informações sobre os indivíduos que os utilizam, muitas vezes violando a privacidade dos mesmos em um ambiente no qual tradicionalmente não há esta preocupação, como a sala de estar ou outro ambiente doméstico. O objetivo deste trabalho é propor uma arquitetura de IPTV que apresente mecanismos capazes de garantir um nível de privacidade maior do que o existente em sistemas de IPTV tradicionais, de maneira a inviabilizar para um observador o correlacionamento entre um usuário do serviço e os conteúdos por ele assistidos. / The increase in media digitalization, broadband availability and technological convergence, allows new services, such as the IPTV (Internet Protocol Television) service, which offers television-related services over a private broadband TCP/IP network. Without proper care, entities or individuals monitoring these services traffic obtain a large amount of information on the service users, and could violate their privacies in an environment in which traditionally there is no such preoccupation, like in a living-room or another domestic environment. The goal of this work is to propose an IPTV architecture capable of guaranteeing a higher privacy level than the existing in traditional IPTV systems, so that it is not viable for an observer to correlate a service user with the content he/she watches.

Tese de doutoramento. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 2009

Television is now changing its traditional distribution forms to being distributed digitally over broadband networks. The recent development of broadband Internet connectivity has made the transition to Internet Protocol Television (IPTV) possible. When changing distribution technique of an existing service, it is important that the new technique does not make the service worse from the user’s point of view. Although a broadband network offers high capacity and has excellent performance there will be occasional packet losses and delays which could negatively influence the user experience of the delivered broadband service. Since bandwidth is a key constraint for video distribution there is a strong incentive for finding schemes to increase bandwidth utilization, especially when distributing high bandwidth IPTV services. In digital video coding it is common to use predictive coding to remove temporal redundancy in video sequences. This technique greatly increases the coding efficiency but makes the sequence more sensitive to information loss or delay. In addition, the use of predictive coding also introduce a inter frame dependency which could make the channel change significantly slower. This thesis addresses two important areas related to bandwidth efficient IPTV distribution, namely error resilience and fast channel change. A method to numerically estimate the decoded objective video quality of scalable coded video is presented and evaluated. The method can be used to estimate objective video quality for a scalable video transmission system subject to packet-loss. The quality gain of temporally scalable video in a priority packet dropping environment is also investigated and quantified. Synchronization Frames for Channel Switching (SFCS) is proposed as a method to code and distribute video with IP-multicast, which can be used to efficiently combat packet-loss, increase bandwidth utilization, and offer a channel change speed up. The performance of SFCS is analyzed and bandwidth estimation expressions are formulated, analytical results are complemented with computer simulations. The results show that SFCS deployed in an IPTV delivery system can significantly lower the bandwidth consumption and speed up the channel change.

IPTV is now offered by several operators in Europe, US and Asia using broadcast video over private IP networks that are isolated from Internet. IPTV services rely ontransmission of live (real-time) video and/or stored video. Video on Demand (VoD)and Time-shifted TV are implemented by IP unicast and Broadcast TV (BTV) and Near video on demand are implemented by IP multicast. IPTV services require QoS guarantees and can tolerate no more than 10-6 packet loss probability, 200 ms delay, and 50 ms jitter. Low delay is essential for satisfactory trick mode performance(pause, resume,fast forward) for VoD, and fast channel change time for BTV. Internet Traffic Engineering (TE) is defined in RFC 3272 and involves both capacity management and traffic management. Capacity management includes capacityplanning, routing control, and resource management. Traffic management includes (1)nodal traffic control functions such as traffic conditioning, queue management, scheduling, and (2) other functions that regulate traffic flow through the network orthat arbitrate access to network resources. An IPTV network architecture includes multiple networks (core network, metronetwork, access network and home network) that connects devices (super head-end, video hub office, video serving office, home gateway, set-top box). Each IP router in the core and metro networks implements some queueing and packet scheduling mechanism at the output link controller. Popular schedulers in IP networks include Priority Queueing (PQ), Class-Based Weighted Fair Queueing (CBWFQ), and Low Latency Queueing (LLQ) which combines PQ and CBWFQ.The thesis analyzes several Packet Scheduling algorithms that can optimize the tradeoff between system capacity and end user performance for the traffic classes. Before in the simulator FIFO,PQ,GPS queueing methods were implemented inside. This thesis aims to implement the LLQ scheduler inside the simulator and to evaluate the performance of these packet schedulers. The simulator is provided by ErnstNordström and Simulator was built in Visual C++ 2008 environmentand tested and analyzed in MatLab 7.0 under windows VISTA.

The distribution of television is currently dominated by three technologies: over-the-air broadcast, cable, and satellite. The advent of IP networks and the increased availability of broadband access created a new vehicle for the distribution of TV services. The distribution of digital TV services over IP networks, or IPTV, offers carriers flexibility and added value in the form of additional services. It causes therefore no surprise the rapid roll-out of IPTV services by operators worldwide in the past few years. IPTV distribution imposes stringent requirements on both performance and reliability. It is therefore challenging for an IPTV operator to guarantee the quality of experience expected by its users, and doing so in an efficient manner. In this dissertation I investigate some of the challenges faced by IPTV distribution network operators, and I propose novel techniques to address these challenges. First, I address one of the major concerns of IPTV network deployment: channel change delay. This is the latency experienced by users when switching between TV channels. Synchronisation and buffering of video streams can cause channel change delays of several seconds. I perform an empirical analysis of a particular solution to the channel change delay problem, namely, predictive pre-joining of TV channels. In this scheme each Set Top Box simultaneously joins additional multicast groups (TV channels) along with the one requested by the user. If the user switches to any of these channels next, switching latency is virtually eliminated, and user experience is improved. The results show that it is possible to eliminate zapping delay for a significant percentage of channel switching requests with little impact in access network bandwidth cost. Second, I propose a technique to increase the resource and energy efficiency of IPTV networks. This technique is based on a simple paradigm: avoiding waste. To reduce the inefficiencies of current static multicast distribution schemes, I propose a semi-dynamic scheme where only a selection of TV multicast groups is distributed in the network, instead of all. I perform an empirical evaluation of this method and conclude that its use results in significant bandwidth reductions without compromising service performance. I also demonstrate that these reductions may translate into significant energy savings in the future. Third, to increase energy efficiency further I propose a novel energy and resource friendly protocol for core optical IPTV networks. The idea is for popular IPTV traffic to optically bypass the network nodes, avoiding electronic processing. I evaluate this proposal empirically and conclude that the introduction of optical switching techniques results in a significant increase in the energy efficiency of IPTV networks. All the schemes I present in this dissertation are evaluated by means of trace-driven analyses using a dataset from an operational IPTV service provider. Such thorough and realistic evaluation enables the assessment of the proposed techniques with an increased level of confidence, and is therefore a strength of this dissertation.

The diploma thesis focuses on the issue of controll network traffic in wireless link. The requirements specification is suggested solution which is implemented and tested in laboratory conditions. The verification is carried out in the WAN network of TS-Hydro, s.r.o. The results are evaluated in the discussion.

This thesis explores how to use gamification for an IPTV platform to increase user engagement. Gamification has been defined as the use of game elements in non-game contexts. This thesis describes the fundamental concepts about gamification and taps on the practical use of these concepts for media and TV consumption. Based on interviews and an online survey we developed and evaluated low-fi prototypes to study some key aspects of Gamification for IPTV solutions. 19 people, not real users, participated in the final evaluation of the last designed low-fi prototype providing qualitative results through an evaluation survey. The result of this case study is a set of game techniques that could be valid for a platform like Ericsson Multiscreen TV, which is the base platform in this thesis. None precedent studies have been found in the research community on the use of gamification on an IPTV platform.

With today's rapid development of technology and IT systems the demand for security and accessibility by both companies and individuals has increased. More and more people want access to their private files and services even when they are not at home. Geographical limitations can be a problem, and some such limitations have been deliberately added to a number of new services on the Internet, such as IPTV and other media services. Today it is neither safe nor appropriate to send sensitive information over public connections, such as the Internet. Because of this, several solutions including IPsec, SSL / TLS, and several other technologies have been developed and implemented. With these, you can create encrypted connections between two endpoints over an internet protocol. This implies in turn that you can access files and services just as you would have done if you actually been at home – you are “Virtually@home”. The report shows a solution to the problem of how to be virtually at home in a simple, cost-effective and safe manner by using a proxy server and a VPN. We review how each of the relevant technologies work and why we believe that this solution is an optimal solution to this problem. / Med dagens snabba utveckling av teknik och informationsteknologiska system har krav ställts på säkerhet och tillgänglighet hos både företag och privatpersoner. Fler och fler vill ha tillgång till sina privata filer och tjänster även när de inte är hemma. Geografiska begränsningar kan vara ett problem, och har medvetet lagts till på ett flertal nya tjänster på internet. såsom IPTV och andra mediaprodukter. Idag är det varken säkert eller lämpligt att skicka känslig information över publika anslutningar, såsom Internet. På grund av detta har ett flertal lösningar såsom IPsec, SSL/TLS, med flera andra tekniker utvecklas och implementerats. Med hjälp av dessa kan man skapa krypterade anslutningar mellan två ändpunkter genom att använda TCP/IP protokollet. Detta går sedan i sin tur att utnyttja för att komma åt filer och tjänster som man skulle gjort om man faktiskt varit hemma – du är Virtually@home. Rapporten visar hur man skapar en lösning till detta problem på ett enkelt, kostnadseffektivt och säkert sätt med hjälp av en proxy och ett VPN. Vi går igenom hur olika tekniker fungerar och varför vi anser att denna lösning är optimal för vårt syfte.

Diplomová práce ?Proměny konkurence na českém telekomunikačním trhu? je zaměřena především na analýzu nedávného turbulentního vývoje telekomunikací v České republice. Se zaměřením na společnost Telefónica O2 Czech Republic,a.s. práce popisuje hlavní faktory, které telekomunikační trh utvářely v uplynulých letech ? zabývá se významnými tržními aliancemi i otázkou regulace odvětví. Závěr práce je věnován hlavním trendům v telekomunikacích, kterými jsou především fixní a mobilní konvergence, VoIP, sítě třetí generace (3G), mobilní virtuální operátoři (MVNO) a televize přes IP (IPTV).