<p>Existing VoD solutions often rely on unicast to distribute content, which leads to a higher load on the VoD server as more nodes become interested in the content. In such case, P2P is an alternative way of distributing content since it makes better use of available resources in the network. In this report, several P2P structures are evaluated from an operators point of view. We believe BitTorrent is the most adequate protocol for a P2P solution in IPTV environments. Two BitTorrent clients have been implemented on an IP-STB as proof of concept to find out whether P2P is suited for IPTV environments. Several tests were conducted to evaluate the performance of both clients and to see if they were able to reach a sufficient throughput on the IP-STB. Based upon the tests and the overall impressions, we are convinced that this particular P2P protocol is well suited for IPTV environments. Hopefully, a client developed from scratch for the IP-STB will offer even greater characteristics.</p><p>Further, we have studied how to share recorded content among IP-STBs. Such a design would probably have many similarities to BitTorrent since a central node needs to keep track of content; the IP-STBs take care of the rest.</p><p>The report also brings up whether BitTorrent is suitable for streaming. We believe that the necessary changes required to obtain such functionality will disrupt the strengths of BitTorrent. Some alternative solutions are presented where BitTorrent has been extended with additional modules, such as a server.</p>

<p>A set top box is an embedded device, much like a computer with limited capabilities. Its main purpose is to decode a video signal and output it to a TV. The set top box market is constantly growing and to be competitive in it, a set top box has to be able to do more than only TV. One way to make an attractive product is to give it an appealing user interface. This thesis is a part of a larger work at the company to find new ways to create graphical user interfaces. Its goal is to investigate what SVG implementations that exits, which one that is most suitable for an integration attempt and then perform the integration.</p><p>Several SVG engines were investigated and one provided by the company was selected for integration. Three ways to integrate the SVG engine were identified. One of these alternatives was to extend the callback interface be- tween the engine and the underlying platform. Because of the good fit with the current architecture this alternative was chosen and implemented. As a part of this investigation a demo application suite of SVG content was also constructed.</p><p>This investigation resulted in a working integration of the chosen SVG engine on the platform. It has also showed that SVG is a suitable language to build graphical user interfaces on set top boxes.</p>

由於網路、電信、多媒體的匯流形成『三網合一』(Triple play)的趨勢，許多相關的應用與服務便應運而生。IPTV(Internet Protocol TV)便是三網合一的應用，綜觀許多研究報告指出，IPTV在未來的成長將會非常驚人。目前全球各地已經陸續推出相關服務，有些國家也已經有相當不錯的成績，但在初期還是有一些困難及挑戰需要克服。以產業價值鏈的角度來看，目前提供IPTV服務的業者共分三類，分別是內容提供者、平台介面提供者以及電信營運商三類，每一類的業者主導IPTV服務都有其優勢及限制，因此本研究希望從產業價值鏈的角度探討IPTV發展的關鍵成功因素。 由於各國有不同的總體環境及產業環境，加上我國目前屬於IPTV產業初期階段，IPTV產業還面臨許多挑戰及困難。以台灣為例，目前提供IPTV服務的業者，在三類產業價值鏈的成員都有代表廠商，因此本研究希望在做全球產業分析的同時，加上對台灣不同價值鏈業者的訪談，做出整理、比較，發展出我國IPTV產業發展的關鍵成功因素命題。

IP networks have become the unified platform that supports a rice and extremely diverse set of applications and services, including traditional IP data service, Voice over IP (VoIP), smart mobile devices (e.g., iPhone), Internet television (IPTV) and online gaming. Network performance and reliability are critical issues in today's operational networks because many applications place increasingly stringent reliability and performance requirements. Even the smallest network performance degradation could cause significant customer distress. In addition, new network and service features (e.g., MPLS fast re-route capabilities) are continually rolled out across the network to support new applications, improve network performance, and reduce the operational cost. Network operators are challenged with ensuring that network reliability and performance is improved over time even in the face of constant changes, network and service upgrades and recurring faulty behaviors. It is critical to detect, troubleshoot and repair performance degradations in a timely and accurate fashion. This is extremely challenging in large IP networks due to their massive scale, complicated topology, high protocol complexity, and continuously evolving nature through either software or hardware upgrades, configuration changes or traffic engineering. In this dissertation, we first propose a novel infrastructure NICE (Network-wide Information Correlation and Exploration) that enables detection and troubleshooting of chronic network conditions by analyzing statistical correlations across multiple data sources. NICE uses a novel circular permutation test to determine the statistical significance of correlation. It also allows flexible analysis at various spatial granularity (e.g., link, router, network level, etc.). We validate NICE using real measurement data collected at a tier-1 ISP network. The results are quite positive. We then apply NICE to troubleshoot real network issues in the tier-1 ISP network. In all three case studies, NICE successfully uncovers previously unknown chronic network conditions, resulting in improved network operations. Second, we extend NICE to detect and troubleshoot performance problems in IPTV networks. Compared to traditional ISP networks, IPTV distribution network typically adopts a different structure (tree-like multicast as opposed to mesh), imposes more restrictive service constraints (both in reliability and performance), and often faces a much larger scalability issue (managing millions of residential gateways versus thousands of provider-edge routers). Tailoring to the scale and structure of IPTV network, we propose a novel multi-resolution data analysis approach Giza that enables fast detection and localization of regions in the multicast tree hierarchy where the problem becomes significant. Furthermore, we develop several statistical data mining techniques to troubleshoot the identified problems and diagnose their root causes. Validation against operational experiences demonstrates the effectiveness of our approach in detecting important performance issues and identifying interesting dependencies. Finally, we design and implement a novel infrastructure MERCURY for detecting the impact of network upgrades on performance. It is crucial to monitor the network when upgrades are made because they can have a significant impact on network performance and if not monitored may lead to unexpected consequences in operational networks. This can be achieved manually for a small number of devices, but does not scale to large networks with hundreds or thousands of routers and extremely large number of different upgrades made on a regular basis. MERCURY extracts interesting triggers from a large number of network maintenance activities. It then identifies behavior changes in network performance caused by the triggers. It uses statistical rule mining and network configuration to identify commonality across the behavior changes. We systematically evaluate MERCURY using data collected at a large tier-1 ISP network. By comparing to operational practice, we show that MERCURY is able to capture the interesting triggers and behavior changes induced by the triggers. In some cases, MERCURY also discovers previously unknown network behaviors demonstrating the effectiveness in identifying network conditions flying under the radar. / text

The media has always gone through changes, starting from the era of the Gutenberg printing press several centuries ago, to the introduction of radio and television in the last 100 years. In the last two decades, Internet and digital technologies have rapidly transformed the media and reshaped how news is gathered and disseminated, and re-defined audiences and their role in the media. Before the Internet, news dissemination was scheduled and periodic, for example the 6pm television bulletin or weekly newspaper. Today news is now global and published in 24/7 round the clock news cycles. At this time, there were clear demarcations between radio, television and newspapers, which were all separate entities. These demarcations have largely fallen away as all media have migrated online to publish on the same platform, using the same elements such as text, audio and video. Increasingly, television is migrating online to the degree that forecasts predict that online television will eclipse traditional TV as we now know it, just as much as online newspapers have eclipsed traditional newspapers. This debate is widely contested In pre-Internet days, the media had distinct demarcations between the media owners, news gatherers (and production people), like journalists, and the audience. These demarcations are blurring as audiences increasingly participate in the media resulting in the emergence of a new breed of journalists; the citizen journalist. This is the most popular term used to describe these new journalists. The dynamic nature of the online platform and functionalities like Web 2.0 made it possible for anyone to publish themselves online, on a blog, on social networking sites or to set up their own website, at very little or no cost. This has spurred a lot of creativity, and the wider public has created vast amounts of content such as video, audio and text and submitted or published them online. Consequently, content creation is no longer the preserve and domain of the media and journalists; the ubiquitous nature of the Internet and the availability of other enabling technologies: inexpensive digital technologies like video cameras, digital cameras and recorders means that anyone with access can now create content and disseminate it. Debates in many parts of the world have suggested that these abilities are catalysts that could spur the public into contributing news and video content of breaking news to the media and help keep the 24/7 round the clock news cycle current. After all, some online social networking sites have already demonstrated that citizens possess the skills to produce and publish video content. At a time when the media is facing financial pressure due to reduced advertising revenues, caused in part by the economic crisis and by the shift to the online platform, there are suggestions that citizens could help newsroom budgets by contributing material. It is against this background of rapid online migration by the media, and the emergence of this new breed of news gatherers, that this research on the Open Newsroom is set. The research topic is not new; a body of research about online migration of the media and the new news ecosystem exists in many other countries. In New Zealand however, this is still an emerging area of for research. This research monitored news bulletins on New Zealand’s two main television news channels, 3 News on TV3 and One News on Television New Zealand for 12 months from early 2008 to late 2009. The idea was to gauge and analyse the amount of content submitted by citizen journalists. The research also looked at a case study which illustrated the potential dangers of using news content submitted by citizen journalists. The research sought the professional opinions of a wide range of decision makers and influential people from the New Zealand media such as editors, journalists and publishers and those involved in the training of journalists in New Zealand. Using a Mini-DV video camera and a digital audio recorder, the researcher filmed and recorded interviewees and edited video clips of the interviews which were then published in the media gallery on the website www.theopennewsroom.com. The interviews sought to find out and discuss the online migration by the media, the new news ecosystem, the public’s participation in the media and the benefits and disadvantages of citizen journalism. To put the research into perspective, the website also carries some research articles and literature reviews on the media. The research findings from the interviews with New Zealand media professionals who participated in the study match trends happening in many countries. While most value the potential benefits of citizen journalists in the news process, some strongly expressed a great deal of skepticism and suspicion regarding news contribution from nontraditional journalism sources. In general, the research offered a series of insights into modern media rather than clear-cut answers

Το αντικείμενο της παρούσας διπλωματικής εργασίας είναι η μελέτη της ψηφιακής τηλεόρασης μέσω πρωτόκολλου Internet, γνωστής και ως IPTV (Internet Protocol TeleVision) με ιδιαίτερη εστίαση στον αποκωδικοποιητή που χρησιμοποιείται για την επίτευξη της τηλεοπτικής μετάδοσης. Αυτός ο αποκωδικοποιητής ονομάζεται Set-Top Box. Στην ουσία το IPTV είναι η μετάδοση τηλεοπτικού σήματος μέσω ευρυζωνικής σύνδεσης που χρησιμοποιεί το πρωτόκολλο IP μέσω ενός ιδιωτικού κλειστού δικτύου και όχι του δημοσίου Internet. Το IPTV θεωρείται το παρόν και το μέλλον όσον αφορά τα είδη τηλεόρασης καθώς ο χρήστης έχει την δυνατότητα για πρόσβαση σε τηλεοπτικά κανάλια με ψηφιακή εικόνα ενώ η δυνατότητα που παρέχουν οι on-demand υπηρεσίες για παρακολούθηση τηλεοπτικού περιεχομένου παντός τύπου την ώρα που επιθυμεί ο χρήστης καθιστά το «πακέτο» πολύ πιο ελκυστικό. Συγκεκριμένα, σε αυτή την διπλωματική εργασία, παρουσιάζεται αρχικά ο ορισμός της δικτυακής τηλεόρασης και γενικά όλων αυτών που συνέβαλλαν στην δημιουργία του IPTV. Κατόπιν γίνεται μια συνοπτική ιστορική αναδρομή στα γεγονότα που οδήγησαν στην μορφή του IPTV όπως την ξέρουμε σήμερα. Έπειτα συγκρίνεται το IPTV με το γνωστό μας Internet TV. Στην συνέχεια γίνεται μια γενική περιγραφή ενός δικτύου IPTV ενώ έπειτα εμβαθύνουμε περισσότερο καθώς περιγράφονται και τεχνικές λεπτομέρειες για ένα τέτοιο δίκτυο. Ακολούθως περιγράφονται οι κωδικοποιήσεις που πραγματοποιούνται αλλά και οι διάφορές τους. Επιπλέον γίνεται ιδιαίτερη αναφορά και ανάλυση στα διάφορα είδη των αποκωδικοποιητών (Set-Top Box) που χρησιμοποιούνται και επισημαίνονται οι διαφορές που έχουν στη δομή και στα χαρακτηριστικά τους. Τέλος γίνεται μια αναφορά στους παρόχους πακέτων IPTV στην Ελλάδα ενώ γίνεται και μια σύγκριση αυτών των πακέτων μεταξύ τους. / The theme of this particular thesis is the study of the digital television via Internet protocol, also known as IPTV (Internet Protocol TeleVision) with special focusing on the decoder which is used in order to achieve television broadcasting. This decoder is called Set-Top Box. Essentially, IPTV is the transmission of television signals over broadband which is using IP protocol through a closed private network and not the public Internet. IPTV is considered to be the present and the future regarding the types of television because the user has the ability to access TV channels with digital view, while the ability provided by on-demand services about watching every type of television content at every time the user wants makes the whole “package” much more attractive. Particularly, in this thesis, is firstly presented the definition of networking TV and generally of all these things which have contributed to the creation of IPTV. Following is a brief historical background to the events that led to the form of IPTV as we know it today. Afterwards, the IPTV is compared to the Internet TV, which is familiar to us. After that, a general description of an IPTV network is taking place and then we go further as technical details of such a network are described. Moreover, the encodings performed and their differences are mentioned. Additionally, there is much reporting and analysis in various types of decoders (Set-Top Box) used and marked the differences they have on their structure and their profile. Finally, there is a reference to IPTV packet providers in Greece and is happening a comparison among these packets.

Existing VoD solutions often rely on unicast to distribute content, which leads to a higher load on the VoD server as more nodes become interested in the content. In such case, P2P is an alternative way of distributing content since it makes better use of available resources in the network. In this report, several P2P structures are evaluated from an operators point of view. We believe BitTorrent is the most adequate protocol for a P2P solution in IPTV environments. Two BitTorrent clients have been implemented on an IP-STB as proof of concept to find out whether P2P is suited for IPTV environments. Several tests were conducted to evaluate the performance of both clients and to see if they were able to reach a sufficient throughput on the IP-STB. Based upon the tests and the overall impressions, we are convinced that this particular P2P protocol is well suited for IPTV environments. Hopefully, a client developed from scratch for the IP-STB will offer even greater characteristics. Further, we have studied how to share recorded content among IP-STBs. Such a design would probably have many similarities to BitTorrent since a central node needs to keep track of content; the IP-STBs take care of the rest. The report also brings up whether BitTorrent is suitable for streaming. We believe that the necessary changes required to obtain such functionality will disrupt the strengths of BitTorrent. Some alternative solutions are presented where BitTorrent has been extended with additional modules, such as a server.

With the standardization of IP Multimedia Subsystem (IMS), the telecommunications scene becomes more and more converged and in the future we will most likely access our services from all kinds of devices and link them together. One important future access method that has so far been left out of the standardization is television. There is a need for Internet Protocol Television (IPTV) to work together with IMS and this thesis focuses on one aspect of that convergence, namely charging. The problem explored in this thesis is if there is an efficient way of charging for IPTV services while taking advantage of the IMS charging functionality and this is done for two aspects of the problem. First, the possiblilty of an efficient Session Initiation Protocol (SIP) signaling schema is investigated and then a good charging Application Programming Interface (API) to be used when developing applications is investigated. The findings of these two investigations are then tested and improved during the implementation of a demo application. This thesis delivers specifications for a signaling schema that enables a Set-Top Box (STB) to pass charging information to an IMS network via INFO requests inside a special charging session. The schema is small and extendable to ensure that it can be modified further on if necessary. The thesis also delivers an encapsulating and intuitive charging API to be used by developers who want to charge for their services.

IPTV (Internet Protocol Television), a new and modern concept of emerging technologies with focus on providing cutting edge high-resolution television, broadcast, and other fascinating services, is now easily available with only requirement of high-speed internet. Everytime a new technology is made local, it faces tremendous problems whether from technological point of view to enhance the performance or when it comes down to satisfy the customers. This cutting edge technology has provided researchers to embark and play with different tools to provide better quality while focusing on existing tools. Our target in dissertation is to provide a few interesting facets of IPTV and come up with a concept of introducing an imaginary cache that can re-collect the packets travelling from streaming server to the end user. In the access node this cache would be fixed and then on the basis of certain pre-assumed research work we can conclude how quick retransmission can take place when the end user responds back using RTCP protocol and asks for the retransmission of corrupted/lost packets. In the last section, we plot our scenario of streaming server on one side and client, end user on the other end and make assumption on the basis of throughput, response time and traffic.

IPTV is a growing form of distribution for TV and media. Reports show that the market will grow from the current 20-30 million subscribers to almost 100 million 2012. IPTV extends the traditional TV viewing with new services like renting movies from your TV. It could also be seen as a bridge between the traditional broadcast approach and the new on demand approach the users are used to from internet. Since there are many actors in the IPTV market that all deliver the same basic functionality, companies must deliver better products that separate them from the competitors. This can be done either through doing things better than the others and/or delivering functionality that others can’t deliver. This thesis project presents the development of a prototype system for serving user generated content in the IPTV middleware Dreamgallery. The developed prototype is a fully working system that includes (1) a fully automated system for transcoding, of video content. (2) A web portal presented with solutions for problems related to user content uploading and administration. (3) Seamless integration with the Dreamgallery middleware and end user GUI, with two different ways of viewing content. One way for easy exploration of new content and a second more structured way of browsing the content. A study of three open source encoding softwares is also presented. The three encoders were subjects to tests of: speed, agility (file format support) and how well they handle files with corrupted data.