Univ., Diplomarbeit, 2004--Frankfurt (Main)

The diploma thesis deals with open source implementations of IMS technology. The theoretical part describes the functioning of IMS and its architecture, including the protocols used, the process of registration and connection establishment, as well as potential security threats to IMS systems. Two open source IMS projects were selected, Open IMS Core and Project Clearwater, on which the work is focused. In its next part, the diploma thesis deals with the description of selected open source IMS projects, this part also includes a description of the implemented security of both projects and a detailed procedure of system installation with any necessary configuration. In its practical part, the diploma thesis focused on performance testing of selected projects using the Abacus 5000 hardware tester. First, initialization tests were performed, which verified the possibility of communication between the tester and the tested projects. Subsequently, it was possible to perform performance testing of selected projects. In performance testing, emphasis is placed on system stability, performance in the area of call set-up speed and response time of SIP messages and speed of user registration in the network, at different load levels. The systems have been tested for both call set-up and user registration. Part of the testing is also the implementation of the flood DoS inviteflood attack and the system's response to the increasing intensity of the attack. The last chapter is devoted to the comparison of selected IMS projects, where the test results are clearly presented. This chapter is partly based on publicly available information, such as the technical documentation of individual projects and possibly publicly available mailing lists. Part of the diploma thesis is also a laboratory task in which the student tries to work with Open IMS Core. The laboratory task focuses on the process of creating a user and his registration in the IMS network, establishing a call between individual users and internal routing in IMS networks. The task focuses mainly on signaling processes within the implemented tasks.

Rich Communication Services(RCS) program is a GSM Association (GSMA) initiative to create inter-operator communication services based on IP Multimedia Subsystem (IMS) . This initiative came up as the Global Telecom Operators ́response to the decline in their revenues and to help compete ’Over The Top’(OTT) service providers such as Viber, whatsapp, etc. RCS is an universal standard, making it inter-operable between mul- tiple service providers unlike OTT services with closed communities. RCS services use IMS as the underlying architecture with a RCS stack imple- mented into Android background service which offers high level API. For the purpose of testing RCS stack functionality which is usually affected by external dependencies like third party vendors, or ISP customizations in real telecommunication scenario, there is a persistent demand for scenario replay tools that can recreate the range of test conditions similar to those experienced in live deployments. There is also a need to evaluate the per- formance of service provided by application servers in the network in-order to predict the factors affecting the RCS service in general. In this work, we propose a tool to address the RCS scenario repro- duction in a test environment. The tool is implemented within an automated test environment with full control on interaction with the RCS stack, hence the ability to replay the scenario in a controlled fashion. To achieve the goal, the tool replays trace interactively with the RCS stack in a stateful manner , it ensures no improper packet generation which is critical feature for test environments where protocol semantics accuracy is fundamental. A detailed demonstration of how the tool can be deployed in test environ- ments is stated. A novel approach is used to validate the effectiveness of the replayed scenario, the sequence of events and states are compared to those from the recorded scenario using a call-back service to indicate the state. The replayed scenario showed strong relationship with the recorded RCS scenario. The paper also presents a performance evaluation of Application service by considering the request-reponse times of Network Registration procedure. The obtained results show that the average time taken for the Registration process is 555 milliseconds and in few instances there exists larger deviations from this average value showing the faulty behavior of the Server which is most crucial during the debugging process for the developers.

Upphovsrätten har som ändamål att skydda innovation och nytänkande genom att ge ensamrätt till litterära och konstnärliga verk. Dessa kan vara mycket betydelsefulla för ett företags ställning på en marknad. Förbudet mot missbruk av dominerande ställning däremot har som ändamål att främja konkurrens genom att förhindra att företag i dominerande ställning snedvrider konkurrensen på marknaden. Det är uppenbart att det kan uppstå en konflikt mellan de olika regelverken eftersom upphovsrätten skyddar en enskild innehavare medan förbudet mot missbruk av dominerande ställning strävar efter att uppnå en öppen och effektiv konkurrens. Ändamålet med det upphovsrättsliga skyddet är inte att hämma konkurrensen, men det kan bli en konsekvens, speciellt om rättighetsinnehavaren är ett företag i dominerande ställning och upphovsrätten utgör ett etableringshinder till marknaden. Vårt fokus i uppsatsen har varit att avgöra när en licensvägran av en upphovsrätt utgör missbruk av dominerande ställning. En upphovsrätt kan vara en viktig faktor vid dominansbedömningen på grund av dess utformning som en exklusiv rätt att förfoga över verket. Däremot är det klargjort av EUD att en upphovsrätt inte automatiskt ger en dominerande ställning på en konkurrensrättsligt relevant marknad, eller ens utgör en presumtion för detta. En helhetsbedömning av alla omständigheter måste alltid göras. Den gränsdragning som måste göras mellan dessa två rättsområden är inte självklar och utfallet får ofta stora ekonomiska konsekvenser för de inblandade företagen. Det finns framför allt två fall, Magill och IMS Health, där EUD har avgjort när licensvägran av en upphovsrätt utgör missbruk och genom dessa fastställt tre faktorer som är avgörande för bedömningen; (1) vägran förhindrade tillkomsten av en ny produkt för vilken det fanns en potentiell efterfrågan hos konsumenterna, (2) vägran kunde inte berättigas av objektiva skäl samt (3) vägran var av beskaffenheten att utestänga all konkurrens från den härledda marknaden. Det har uppstått en konflikt mellan SJ och MTR på grund av SJ:s vägran att låta MTR sälja biljetter via bokningssystemet på www.sj.se. MTR hävdar att SJ har missbrukat sin dominerande ställning på marknaden genom detta agerande. Vi har undersökt huruvida SJ har en dominerande ställning på marknaden och om bokningssystemet på www.sj.se är upphovsrättsligt skyddat. Slutligen har vi med tillämpning av ovanstående faktorer undersökt huruvida SJ:s beteende utgör missbruk av dominerande ställning.

Inductive Monitoring Systems (IMS) are the newest form of health monitoring available to the aerospace industry. IMS is a program that builds a knowledge base of nominal state vectors from a nominal data set using data mining techniques. The nominal knowledge base is then used to monitor new data vectors for off-nominal conditions within the system. IMS is designed to replace the current health monitoring process, referred to as model-based reasoning, by automating the process of classifying healthy states and anomaly detection. An IMS prototype was designed and implemented in MATLAB. A verification analysis then determined if the IMS program could connect to a CubeSat in a testing environment and could successfully monitor all sensors on board the CubeSat before in-flight use. This program consisted of two main algorithms, one for learning and one for monitoring. The learning algorithm creates the nominal knowledge bases and was developed using three data mining algorithms: the gap statistic method to find the optimal number of clusters, the K-means++ algorithm to initialize the centroids, and the K-means algorithm to partition the data vectors into the appropriate clusters. The monitoring algorithm employed the nearest neighbor searching algorithm to find the closest cluster and compared the new data vector with the closest cluster. The clusters found were used to establish the knowledge bases. Any data vector within the boundaries of the clusters was deemed nominal and any data vector outside the boundaries was deemed off-nominal. The learning and monitoring algorithms were then adapted to handle the data format used on a CubeSat and to monitor the data in real time. The developed algorithms were then integrated into a MATLAB GUI for ease of use. The learning and monitoring algorithms were verified with a 2-dimensional data set to ensure that they performed as expected. The final IMS CubeSat prototype was verified using 56-dimensional emulated data packages. Both verification methods confirmed that the IMS ground- based prototype was able to successfully identify all off-nominal conditions induced into the system.

La taxation est l'une des activités principales de la livraison des services de télécommunications. C'est la machine de génération de revenus pour l'opérateur. Le concept de taxation a connu des évolutions pour s'adapter aux évolutions des réseaux, des services et applications, des médias et comportements des utilisateurs. Les réseaux convergent vers le tout-IP concrétisé par le paradigme de l'IMS, mettant ainsi la qualité de service au coeur des préoccupations des opérateurs. Les applications peuvent intégrer plusieurs services en même temps et sont livrées dans un contexte de session permettant de véhiculer plusieurs flux, contenus et médias en même temps. Les médias sont devenus de plus en plus riches avec la combinaison de la voix, du texte, de l'image et de la vidéo dans un même contenu livré à l'utilisateur. Le comportement des utilisateurs par rapport au produit de télécommunications a changé d'un moyen de communication de base à un outil d'information et de divertissement. Ceci rend la qualité d'expérience des applications un facteur de réussite des opérateurs et une taxation équitable est l'un des premiers paramètres à considérer afin d'améliorer l'expérience client.Ce travail consiste à adresser la complexité de la taxation des services de télécommunication d'une manière équitable, sans pénalisation pour l'utilisateur ni perte de revenu pour l'opérateur. Pour ce faire nous proposons une modélisation des applications multimédia complexes. Puis nous construisons la fonction de tarification qui est la fonction principale du module de taxation. Cette fonction permettra d'adresser la problématique de la taxation équitable dans le contexte du tout-IP. / Charging of services is one of the most important activities of service delivery in telecommunications. It is the revenue generator engine for operators. The concept of charging has evolved with the evolution of networks, applications, media types and end-user behaviors. Telecommunications networks have converged to All-IP with the introduction of IP Multimedia Subsystem. Hence, the Quality of Service has become a core concern of operators. Applications have become richer, including many services, contents and media types in a single session. A variety of content could be used by end-user, voice, data, text, image, and video. New content could be created with the combination of two or more basic content types. The behavior of end users in front of telecommunications services has evolved from a basic communication tool to information and entertainment tool. Consequently, the Quality of Experience is standing in the first stage to scale the success of one application. In this new context, a clear and fair charging is one of the first parameters to consider in Quality of Experience building. In our work, we will address the complexity of charging of new generation of telecommunications services. First, we propose a modeling of these new complex multimedia applications. Then, we construct the Rating Function which is the main module of charging. This function will address accurately the question of fair charging in All-IP context.

<p>Naučni cilj istraživanja u okviru doktorske disertacije je kompleksnog karaktera, koji se manifestuje:<br />identifikacijom performansi transportne organizacije, koje se mogu smatrati značajnim za uspe&scaron;no upravljanje organizacijom i prevođenje iz postojećeg u željeno stanje<br />identifikacijom SMS, kojom su posmatrane transportne organizacije implementirale i koje su postale sastavni delovi menadžment sistema organizacije<br />istraživanjem načina na koje je moguće meriti uticaj primene SMS, odnosno IMS na performanse organizacije, sa ciljem da se istovremeno ukaže na slabosti i mogućnosti razvoja organizacije.<br />Polazeći od formulisanih ciljeva, definisana je orginalna metodologija, postupak kojim se dokazuje opravdanost uspostavljenih osnovnih hipoteza disertacije, čija su&scaron;tina je da modeli integrisanih sistema menadžmenta imaju uticaja na performanse transportnih organizacija.</p> / <p>Scientific aim of this research is complex and it is manifested by following:<br /> Identification of transport organization performances which can be considered as important for succesful organization management and shift from existing to favorable condition;<br /> Identification of SMS which transport organizations implemented and which became parts of organization management system;<br /> Research of ways on which is possible to measure effect of SMS application or IMS to organization performances with aim to emphasize defeciencies and possibilities for organization development.<br />According to formulated aims, original methodology is defined. Is is practice which justifies main hypotheses of disertation. Their purpose is to make integrated management system models effective for performances of transport organizations.</p>

This thesis describes protocols used in IP Multimedia Subsystem (IMS) networks. Freely available implementations of IMS system are described. The main goal is to describe design and implementation of a tool for analyzing communication between users and IMS system. The tool seeks and decodes signaling messages. These messages are analyzed for information about sessions which are necessary for session monitoring and accounting. Final gathered information are exported in a form of extended NetFlow/IPFIX records. We used open-source Open IMS Core implementation for building IMS network and creating test data. As endpoints we used another open-source application for Android OS called IMSDroid.

This thesis deals with an introduction of new functionalities in communication via IP Multimedia Subsystem (IMS) at the beginning. There are described functions of each part and introduced protocols which are used by this system. Thesis presents the method of positioning with Global Positioning System (GPS) together with methods for the distance measuring of two points on the Earth. Services provided by IMS are developed in Service Development Studio which is shortly mentioned too. The developed service is divided into two parts: a client side part and a server side part, which is formed like a servlet. This program component, which is running on server is mentioned at the end of teoretical part. The procedure of service creating, setup and functions are in description of the created service, which provides informations based on geographical coordinates to user, is described after the teoretical part.

This master's thesis describes suggestion of an application designed for marketing research utilizing development environment of Ericsson company using services IMS and SIP. The essay examines the options offered by programming languages Java, PHP, of the database system MySQL, language XML and SIP messages. A creation of a server - client pair of applications used for marketing research was the main focus of this paper was. These applications can be used for distribution of questionnaires and their subsequent collection by the server, which allows for an output of statistics based on the acquired data. It is not necessary to work with all the applications, it is possible to filter based on one or more categories and only have the selected questionnaires sent. The questionnaire results will be shown in a form of straightforward table in the server’s console window. The XML language has been selected for the storing the questionnaires. All technologies and methods used are described within the essay. An integral part of the module is also the creation of a database of questions, which has been created in the PHP programming language. MySQL has been used as a database server. The application output is an XML file, which can be used as an input for an IMS server. The results of this thesis are demonstrated using screenshots taken during the application testing.