Eine kurze Einführung zu "Voice over IP" (dem Telefonieren über Datennetze). Es wird ein Überblick über technische Anforderungen und Lösungen geben. Behandelte Gebiete sind Audio-Codecs, das Transportprotokoll RTP sowie die Signalisierungsdienste SIP und H.323.

Customer Premises Equipment (CPE) management is underestimated by the CPE vendors and services providers while it is in fact one of the most important aspects to ensure the high quality of service. Many people still think CPE management is the same as network management. Thus, they use the Simple Network Management Protocol (SNMP) to manage their CPEs. However, SNMP alone was thought not to scale nor to support the provisioning of the types of services which internet services providers must support today. This thesis highlights the importance of CPE management, how it is implemented using the TR-069; a CPE management protocol defined by the DSL Forum, and how a management system can be used for VoIP service management, and whether a CPE should implement TR-069 or SNMP as the management system to support. In the addition, the TR-069 will be compared against the SNMP to determine which one is more suitable for CPE management. An interesting conclusion is that while TR-069 does have some advantages over SNMP for managing services rather than simply managing the device, these advantages are not a large as initially believed nor has TR-069 avoided the problem of proprietary management information which SNMP has demonstrated. / Customer Premises Equipment (CPE) skötseln är undervärderad av CPE försäljarna och tjänste leverantörerna meddans det faktiskt är en av de mest viktiga aspekterna för att tillförsäkra hög quality of service. Många personer tror fortfarande att CPE skötseln är det samma som att sköta ett nätverk. Så, de använder Simple Network Management Protocol (SNMP) för att sköta deras CPE:er. Emellertid, SNMP ensamt var inte tänkt att skala eller att ge stöd vid försörjning av typer av tjänster som internet tjänst leverantörer måste stödja idag. Den här avhandlingen framhäver det väsentliga med CPE skötsel, hur det implementeras vid användande av TR-069; ett CPE skötsel protocol definerat av DSL forum, och hur detta administrations system kan användas för att sköta VoIP tjänster. Tilläggande så kommer avhandligen att jämföra TR-069 och SNMP för att bestämma vilken av dem som är mer lämplig för CPE administration. En intressant sammanfattning är att meddans TR-069 har några fördelar över SNMP för att sköta tjänster hellre än att enkelt sköta enheten, dessa fördelar är inte så stora som man trott från början. Dessutom, TR-069 ser inte ut att kunna övervinna problemet med privatägd (användande av privat MIB) information som SNMP har demonstrerat.

Today, the telecommunication world is focused on mobility. This is popular because since the 1990s most people have integrated their mobile phones into their life. A new factor is the rise of the voice over IP(VoIP) technology, with VoIP over Wireless LANs (WLANs) as the clear next growth area for mobile communications. The purpose of this thesis was to understand how to save power based upon changing when some operations are performed in a VoIP client. In order to do this, we decided to port minisip to an HP iPAQ 5500 Personal Digital Assistant (PDA), in order to explore some of the issues of running such a client on a PDA - due to its constraints with regard to storage, processing power, and battery power. Minisip is a SIP open source user agent running on Linux and Windows. This thesis builds upon earlier theses which showed that minisip can offer a secure communications platform with the latest functions which are desired in a mobile personal VoIP system. However, most of these earlier theses utilized desktop, laptop, or server based system, i.e., with few resources constrains. The focus of this thesis was to examine the case of a highly constrained user platform such as an iPAQ. / Dagens telekommunikationssystem fokuserar på mobilitet. Detta har blivit populärt under 90-talet då mobilitet blev naturligt integrerad i människans vardagliga liv i form av exempelvis mobiltelefoner. Voice over IP (VoIP) har blivit en stor del av dagen teknik där trådlösa system Wireless LANs (WLANs) har blivit en större del av mobilkommunikation. Målet med denna rapport är att förstå hur strömförbrukningen kan minimeras genom att utföra vissa operationer med hjälp av en VoIP-klient. För att åstadkomma detta porterade vi minisip, en SIP agent som är baserad på öppen källkod och körs på Linux och Windows, till en HP iPAQ 5500, en så kallad Personal Digital Assistant (PDA). Vi valde PDAn för att kunna utforska de begränsningar den medför i form av lagringsutrymme, processorkapacitet, och batteri. Denna rapport bygger vidare på tidigare rapporter som visar att minisip kan erbjuda en säker kommunikationsplattform med de senaste funktionerna som önskas i mobila VoIPsystem. De flesta av dessa tidigare rapporter baseras på system med få begränsningar rörande resurser såsom stationära- eller bärbara datorer samt serverbaserade system. Denna rapports fokus är att utforska detta fall i en miljö med större begränsningar på resurser som till exempel en iPAQ.

Puppets have been entertaining, educating, and mesmerizing American audiences since the birth of our nation. Both in live theatrical events and TV/film, audiences have watched puppeteers bring their puppet characters to life with clever voice quality choices, unique characterizations, and vivid visual designs. This thesis is a case study that first borrows insight from cartoon character designers, animators, and voiceover actors to provide considerations for voice quality choices, characterizations, and design elements when creating a new puppet character. It then investigates the connections that exist between those three elements once a puppet is fully realized. In order to identify these connections, a test was developed in which participants were asked to use a set of blank puppet heads/bodies and a variety of facial features to each build a unique character and then provide their puppets with a unique character voice. The data collected from the test was then deconstructed and analyzed by comparing each included design element to specific Estill Voice Training System™ vocal attributes identified within each individual puppet character's voice to find where connections occurred. The goal of this thesis is to provide a systematic method for creating vibrant and rich original puppet characters.

Approved for public release, distribution is unlimited / Recent advances in information technology communications have brought about increases in bandwidth and processing speeds to encourage the growth of Internet Protocol Telephony (IPT), a method of transmitting voice conversations over data networks. Many organizations are replacing portions of their traditional phone systems to gain the benefits of cost savings and enhanced feature sets through the use of IPT. The Coast Guard has an interest in exploiting this technology, and has taken its first steps by implementing IPT at Headquarters Support Command in Washington D.C. This thesis investigates the successful implementation practices and security policies of commercial, educational, and government organizations in order to create recommendations for IPT security policies and implementation practices relevant to the Coast Guard. It includes the discussion of the public switched telephone network, an overview of IPT, IPT security issues, the safeguards available to counter security threats, the tradeoffs (e.g., voice quality, cost) required to mitigate security risks, and current IPT security policy and implementation guidance. It is supported by the study and analysis of the IPT system at Coast Guard Headquarters. The Coast Guard gains an understanding of the advantages, limitations, and security issues that it will face as it considers further implementation of IPT. / Lieutenant, United States Coast Guard

Les récentes avancées technologiques permettent désormais la fabrication de terminaux mobiles de plus en plus compacts et dotés de plusieurs interfaces réseaux. Le nouveau modèle de consommation de médias se résume par le concept "Anytime, Anywhere, Any Device" et impose donc de nouvelles exigences en termes de déploiement de services ubiquitaires. Cependant la conception et le developpement de réseaux ubiquitaires et convergents de nouvelles générations soulèvent un certain nombre de défis techniques. Les standards actuels ainsi que les solutions commerciales pourraient être affectés par le manque de considération du contexte utilisateur. Le ressenti de l'utilisateur concernant certains services multimédia tels que la VoIP et l'IPTV dépend fortement des capacités du terminal et des conditions du réseau d'accès. Cela incite les réseaux de nouvelles générations à fournir des services ubiquitaires adaptés à l'environnement de l'utilisateur optimisant par la même occasion ses resources. L'IP Multimedia Subsystem (IMS) est une architecture de nouvelle génération qui centralise l'accès aux services et permet la convergence des réseaux fixe/mobile. Néanmoins, l'évolution de l'IMS est nécessaire sur les points suivants :- l'introduction de la sensibilité au contexte utilisateur et de la PQoS (Perceived QoS) : L'architecture IMS ne prend pas en compte l'environnement de l'utilisateur, ses préférences et ne dispose pas d'un méchanisme de gestion de PQOS. Pour s'assurer de la qualité fournit à l'utilisateur final, des informations sur l'environnement de l'utilisateur ainsi que ses préférences doivent transiter en cœur de réseau afin d'y être analysés. Ce traitement aboutit au lancement du service qui sera adapté et optimisé aux conditions observées. De plus pour le service d'IPTV, les caractéristiques spatio-temporelles de la vidéo influent de manière importante sur la PQoS observée côté utilisateur. L'adaptation des services multimédias en fonction de l'évolution du contexte utilisateur et de la nature de la vidéo diffusée assure une qualité d'expérience à l'utilisateur et optimise par la même occasion l'utilisation des ressources en cœur de réseau.- une solution de mobilité efficace pour les services conversationnels tels que la VoIP : Les dernières publications 3GPP fournissent deux solutions de mobilité: le LTE propose MIP comme solution de mobilité alors que l'IMS définit une mobilité basée sur le protocole applicatif SIP. Ces standards définissent le système de signalisation mais ne s'avancent pas sur la gestion du flux média lors du changement d'interface réseau. La deuxième section introduit une étude comparative détaillée des solutions de mobilité dans les NGNs.Notre première contribution est la spécification de l'architecture globale de notre plateforme IMS sensible au contexte utilisateur réalisée au sein du projet Européen ADAMANTIUM. Nous détaillons tout d'abord le serveur MCMS intelligent placé dans la couche application de l'IMS. Cet élément récolte les informations de qualité de services à différents équipements réseaux et prend la décision d'une action sur l'un de ces équipements. Ensuite nous définissons un profil utilisateur permettant de décrire son environnement et de le diffuser en coeur de réseau. Une étude sur la prédiction de satisfaction utilisateur en fonction des paramètres spatio-temporels de la vidéo a été réalisée afin de connaître le débit idéal pour une PQoS désirée.Notre deuxième contribution est l'introduction d'une solution de mobilité adaptée aux services conversationnels (VoIP) tenant compte du contexte utilisateur. Notre solution s'intègre à l'architecture IMS existante de façon transparente et permet de réduire le temps de latence du handover. Notre solution duplique les paquets de VoIP sur les deux interfaces actives pendant le temps de la transition. Parallèlement, un nouvel algorithme de gestion de mémoire tampon améliore la qualité d'expérience pour le service de VoIP. / The latest advances in technology have already defied Moore’s law. Thanks to research and industry, hand-held devices are composed of high processing embedded systems enabling the consumption of high quality services. Furthermore, recent trends in communication drive users to consume media Anytime, Anywhere on Any Device via multiple wired and wireless network interfaces. This creates new demands for ubiquitous and high quality service provision management. However, defining and developing the next generation of ubiquitous and converged networks raise a number of challenges. Currently, telecommunication standards do not consider context-awareness aspects for network management and service provisioning. The experience felt by the end-user consuming for instance Voice over IP (VoIP) or Internet Protocol TeleVision (IPTV) services varies depending mainly on user preferences, device context and network resources. It is commonly held that Next Generation Network (NGN) should deliver personalized and effective ubiquitous services to the end user’s Mobile Node (MN) while optimizing the network resources at the network operator side. IP Multimedia Subsystem (IMS) is a standardized NGN framework that unifies service access and allows fixed/mobile network convergence. Nevertheless IMS technology still suffers from a number of confining factors that are addressed in this thesis; amongst them are two main issues :The lack of context-awareness and Perceived-QoS (PQoS):-The existing IMS infrastructure does not take into account the environment of the user ,his preferences , and does not provide any PQoS aware management mechanism within its service provisioning control system. In order to ensure that the service satisfies the consumer, this information need to be sent to the core network for analysis. In order to maximize the end-user satisfaction while optimizing network resources, the combination of a user-centric network management and adaptive services according to the user’s environment and network conditions are considered. Moreover, video content dynamics are also considered as they significantly impact on the deduced perceptual quality of IPTV services. -The lack of efficient mobility mechanism for conversational services like VoIP :The latest releases of Third Generation Partnership Project (3GPP) provide two types of mobility solutions. Long-Term Evolution (LTE) uses Mobile IP (MIP) and IMS uses Session Initiation Protocol (SIP) mobility. These standards are focusing on signaling but none of them define how the media should be scheduled in multi-homed devices. The second section introduces a detailed study of existing mobility solutions in NGNs. Our first contribution is the specification of the global context-aware IMS architecture proposed within the European project ADAptative Management of mediA distributioN based on saTisfaction orIented User Modeling (ADAMANTIUM). We introduce the innovative Multimedia Content Management System (MCMS) located in the application layer of IMS. This server combines the collected monitoring information from different network equipments with the data of the user profile and takes adaptation actions if necessary. Then, we introduce the User Profile (UP) management within the User Equipment (UE) describing the end-user’s context and facilitating the diffusion of the end-user environment towards the IMS core network. In order to optimize the network usage, a PQoS prediction mechanism gives the optimal video bit-rate according to the video content dynamics. Our second contribution in this thesis is an efficient mobility solution for VoIP service within IMS using and taking advantage of user context. Our solution uses packet duplication on both active interfaces during handover process. In order to leverage this mechanism, a new jitter buffer algorithm is proposed at MN side to improve the user’s quality of experience. Furthermore, our mobility solution integrates easily to the existing IMS platform.

The diploma thesis Contemporary Czech film trailer and its role in the promotion of the film in the context of foreign production deals with the film trailer. The first part deals with the development of the film trailer abroad, particularly in the United States of America. It describes every single time period up to the present day and outlines the future trends in its development. The second part comprehensively analyzes all components of cinematic trailer. It describes the process of making movie trailers, classifies it in the film marketing communication mix and examines its role in the film promotion. It refers to manipulative function of trailer and deals with its control. Finally, describes the process of distribution trailer and shows the various distribution channels. All of these issues compare the situation in the U.S. and the Czech Republic. The final section focuses on the Czech film trailer. First, it maps its history from the beginning to the present. Then it puts these findings into the context of the Czech film history and the history of the Czech movie promotion. Further thesis will focus on the current situation in the Czech trailer. Analyzes it from the perspective of film critics and trailer makers and presents all factors influencing the form of trailers. In conclusion, the...

The interactive and non-linear aspects of video games bring forth the problem of repetition.In game sound, dialogue is particularly susceptible to repetition because of our hearing’ssensitivity to human speech. The most common way to avoid repetition in game dialogue isto record multiple takes of every phrase as to have several naturally varied samples, whereasthis study explores the possibility to create these natural variations by manipulation of pitchand/or time of one recorded phrase using a readily available software. A listening test wasconducted where 23 subjects rated the variation, naturalness and artifacts of a recordedspoken phrase where three altered versions manipulated by altering the pitch, timing and bothpitch and timing where compared to the original recording, examining which manipulationtype yielded the most variation while also considering the naturalness and artifacts. Arepeated measures factorial ANOVA and pairwise comparisons showed a significantdifference between all manipulation types regarding the three dependent variables. Theresults show that the pitch manipulated sample had the best compromise between perceivedvariation, naturalness and artifacts, and would therefore be the recommended method forcreating variation of recorded dialogue.

Made available in DSpace on 2016-04-04T18:31:20Z (GMT). No. of bitstreams: 1 Alessandra B Bandeira.pdf: 1200038 bytes, checksum: 316684811248760f05faf3fdda1844f3 (MD5) Previous issue date: 2007-10-30 / This work investigates VoIP (Voice over IP) performance over WLAN (WVoIP) through qualitative and quantitative point of view, considering degradation in indoor environment. The results was obtained through a channel emulator to produce the Weibull distribution. Measurements results with a robot showed that this distribution is adequate to represent WLAN environment instability. The test utilized the CODECs (Coder Decoder) G711 and GSM (Global System for Mobile Communications). The work presents results that indicate the effect of the instability of wireless environment in the VoIP performance. The results indicate a significant variation of voice quality, considering the severity of the phenomena emulated. The behaviors of the CODECs are evaluated considering the different characteristics of bandwidth and robustness. / O trabalho investiga de forma quantitativa e qualitativa o desempenho de VoIP (Voz sobre IP) em uma rede WLAN (Wireless Local ?rea Network), denominado WVoIP, (Wireless VoIP) considerando degrada??o em ambiente indoor. Para atingir esse objetivo foram realizados testes utilizando um emulador de canal capaz de produzir fen?menos de propaga??o com distribui??o de Weibull. Medidas mostram que esta distribui??o ? adequada para avalia??o de instabilidade em redes WLANs. S?o utilizados dois codecs de voz: G711 e GSM (Global System for Mobile Communications). O trabalho apresenta resultados que indicam o efeito dos fen?menos de instabilidade das redes sem fio no desempenho de VoIP, que revelam varia??es significativas na qualidade de voz em fun??o da intensidade dos fen?menos emulados. S?o analisadas as quest?es relativas aos codecs de voz que possuem caracter?sticas de banda e robustez diferentes.

Made available in DSpace on 2016-04-04T18:31:26Z (GMT). No. of bitstreams: 1 Adenilson Boccato de Almeida.pdf: 2733171 bytes, checksum: 5b2d37bdad4b16ff26ccb172bbd6fbfc (MD5) Previous issue date: 2008-12-18 / This dissertation examines the quality of the transmission of VoIP (Voice over IP) in wireless LAN (Local Area Network Wireless). To achieve this objective tests were performed on the bench using voice codecs G729, G711, G723 and GSM analyzing characteristics of delay and loss of packets. The paper presents results that indicate the effect of the phenomena of instability of wireless networks in the performance of VoIP. These variations show significant changes in the quality of voice depending on the used environment and the distance between the transmitter and receiver. / Esta disserta??o analisa a qualidade da transmiss?o do VoIP (Voz sobre IP) em rede WLAN (Wireless Local ?rea Network). Para atingir esse objetivo foram realizados testes em bancada utilizando os codecs de voz G729, G711, G723 e GSM analisando suas caracter?sticas de atraso e perda de pacotes. O trabalho apresenta resultados que indicam o efeito dos fen?menos de instabilidade das redes sem fio no desempenho do VoIP. Essas varia??es revelam altera??es significativas na qualidade da voz em fun??o do ambiente utilizado e da dist?ncia entre o emissor e receptor.