I detta examensarbete undersöks hur nya byggmaterial dämpar radiosignaler samt vilken miljöpåverkan eventuella signalförbättrande lösningar kan ha. Miljömedvetenhet och hållbara tekniska lösningar är måsten då planering av nya byggnader görs. Detta sätter stor press på byggföretagen som har stora krav på sig att tänka energieffektivitet och långsiktighet. Nya material och byggtekniker syftar till att reducera den mängd energi som krävs för uppvärmning av bostäder. En konsekvens av detta är att radiosignalerna dämpas och att de boende inte har en fullgod mottagning på sina mobiltelefoner inomhus. För att komma runt mottagningsproblematiken öppnas ett fönster alternativt balkongdörren för att få acceptabel mottagning. De energiförluster som uppstår på grund av vädring är en viktig parameter att ta i beaktande. En minskning skulle kunna vara ett incitament för en fastighetsägare att vilja satsa på mottagningsförbättrande åtgärder. För att bättre få en förståelse för problemen gjordes mätningar på nybyggda hus som ansågs representativa. Resultaten av mätningarna användes senare i matematiska modeller för att analysera och för att skapa förståelse för problemet. Resultatet visar tydlig att den gamla schablonen för förlust på 15 dB inte funkar på nya energieffektiva fastigheter. I rapporten förslås därför ett nytt värde på 23 dB som analysen av det insamlade datat visar. Yttäckningsmodeller gjorda med det nya värdet visat på en minskning av täckningsområdet från basstationen. / The goal of this thesis is to examine the attenuation of new building materials on radio signals and the environmental effects that any signal improving solution might have. Environmental awareness and sustainable solutions are key issues when planning new buildings. Energy conservation and planning for the future puts pressure on companies to rethink the way they plan and construct new buildings. New materials and new techniques are required to reduce the amount of energy it takes to heat our buildings. One unfortunate drawback is the attenuation these new materials have on radio signals. This creates problems for the tenants as they are no longer able to use their mobile telephones indoors. To get around that problem a windows or door to the balcony is opened to get an acceptable reception. The energy losses that occur as a result are important to consider. A decrease in these energy losses might serve as an incentive for real estate owners to invest in signal improving solutions for their buildings. To get a better understanding of the problem, tests were performed in buildings that incorporate these new materials and techniques. The results of these tests were then used in mathematical models to analyze and to get a better understand the size of the problem. The results show a significant difference when compared to values used in previous calculations where 15dB was seen as a reasonable. This report suggest that the old value is changed to 23dB as seen in the analysis of the data collected. When this new value is used in the surface coverage models, the decrease in cell coverage from the base station becomes evident.

The emergence of resource-rich mobile devices and smart vehicles has paved the way for Urban Sensing. In this new paradigm, users sense their environment and become part of an unprecedented large-scale network of sensors, with extensive spatial and temporal coverage, that enables the collection and dissemination of real-time information, practically, from anywhere. Urban sensing can facilitate the deployment of innovative applications that can address the ever-growing concerns for citizens’ well-being. Nevertheless, the openness of such systems (ideally anyone can participate) and the richness of the data users contribute unavoidably raise significant concerns for both the security of urban sensing applications and the privacy of the participating users. In this thesis we consider different urban sensing application domains: vehicular communication networks, intelligent transportation systems and environmental monitoring applications. We begin with a detailed analysis of the security and privacy requirements of these applications domains. Our objective is to protect users from the system (by ensuring their anonymity and privacy) and urban sensing systems from malicious users (by holding malicious users accountable of their actions). This is not straight-forward; anonymity may tempt malicious user behavior, compromising the reliability of the entire urban sensing system.Towards that, we design and implement secure and privacy-preserving identity management systems that can accommodate these requirements. We demonstrate their efficiency, practicality, and scalability through extensive experimental evaluations. Furthermore, we formally evaluate formally their security and privacy preserving properties. / <p>QC 20141001</p>

In current wireless communication systems, demands for extremely high data rates, along with spectrum scarcity at the microwave bands, make the millimeter wave (mmWave) band very appealing to provide these extremely high data rates even for a massive number of wireless devices. MmWave communications exhibit severe attenuation, vulnerability to obstacles (called blockage), and sparse-scattering environments. Moreover, mmWave signals have small wavelengths that allow the incorporation of many antenna elements at the current size of radio chips. This leads to high directivity gains both at the transmitter and at the receiver, directional communications, and, more importantly, possible noise-limited operations as opposed to microwave networks that are mostly interference-limited. These fundamental differences between mmWave networks and legacy communication technologies challenge the classical design constraints, objectives, and available degrees of freedom. The natural consequence is the necessity of revisiting most of the medium access control (MAC) layer design principles for mmWave networks, which have so far received less attention in the literature than physical layer and propagation issues. To address this important research gap, this thesis investigates the fundamental MAC layer performance metrics, including coverage, fairness, connection robustness, collision probability, per-link throughput, area spectral efficiency, and delay. The original analysis proposed in this thesis suggests novel insights as to the solutions for many MAC layer issues such as resource allocation, interference management, random access, mobility management, and synchronization in future mmWave networks. A first thread of the thesis focuses on the fundamental performance analysis and mathematical abstraction of mmWave wireless networks to characterize their differences from conventional wireless networks, i.e., high directivity, line-of-sight communications, and occurrence of deafness (misalignment between transmitters and receivers). A mathematical framework to investigate the impact of beam training (alignment) overhead on the throughput is established, which leads to identify a new alignment-throughput tradeoff in mmWave networks. A novel blockage model that captures the angular correlation of line-of-sight conditions using a new notion of "coherence angle" is proposed. The coverage and delay of directional cell discovery are evaluated, and an optimization approach to maximize long-term throughput of users with fairness guarantees is proposed. In addition, this thesis develops a tractable approach to derive the collision probability, as a function of density of the transmitters, transmission power, density and size of the obstacles, operating beamwidth, and sensitivity of the receiver, among the main parameters. The collision probability allows deriving closed-form expressions for the per-link and network throughput of mmWave networks, and thereby identifying that, contrary to mainstream belief, these networks may exhibit a non-negligible transitional behavior of interference from a noise-limited to an interference-limited regime. The second thread of the thesis builds on the previous fundamental performance analysis and modeling to establish new, efficient MAC protocols. The derived collision probability is used to evaluate per-link throughput, area spectral efficiency, and delay performance of common MAC protocols such as TDMA and slotted ALOHA, and to provide a fundamental comparison between pros and cons of contention-free and contention-based MAC protocols. The results suggest the use of on-demand interference management strategy for future mmWave cellular networks and collision-aware hybrid MAC protocols for mmWave ad hoc networks to reliably deliver messages without sacrificing throughput and delay performance. Moreover, the transitional behavior, together with significant mismatch between transmission rates of control and data messages, imposes the development of new hybrid proactive and reactive control plane architecture. This thesis identifies the prolonged backoff time problem, which happens in mmWave networks due to blockage and deafness, and proposes a new collision notification signal to solve this problem. Motivated by the significant mismatch between coverage of the control and data planes along with delay analysis of directional cell search, a novel two-step synchronization procedure is proposed for mmWave cellular networks. Also, the impact of relaying and multi-hop communication to provide reliable mmWave connections, to alleviate frequent handovers, and to reduce the beam training overhead is investigated. The investigations of this thesis aim to demystify MAC layer performance of mmWave networks and to show the availability of many new degrees of freedom to improve the network performance, e.g., in terms of area spectral efficiency, energy efficiency, robustness, delay, coverage, and uniform quality of service provisioning. The results reveal many special behaviors of mmWave networks that are largely ignored in design approach of the current mmWave networks. Given that the standardization of mmWave wireless cellular networks has not started as yet, and that existing standards of mmWave ad hoc networks are highly sub-optimal, the results of this thesis will provide fundamental design guidelines that have the potential to be very useful for future mmWave standardizations. / <p>QC 20150907</p>

Web Call Example Application from Ericsson Developer Connection is an application that hosted at a web server and supplies functionality of VoIP phone calls. Users can access the service from desktop browser, mobile phone browser or Java ME Client. Users can also manage their contact books. Each user can have more than one VoIP service accounts, so they can choose the cheapest on when they make phone call. The Web Call Example Application supports two kinds of VoIP phone call connection: Relay Call and Third Party Call. For the Third Party Call there are four different implementations: Call Transfer, SDP Swap, Re-invite and Web Client. This master thesis introduces the theory of third party call and the implementation of Web Call Example Application.

This report is the result of a masters degree project conducted at the Department of Teleinformatics at the Royal Institute of Technology during the autumn 1995. The area investigated is the Mobile Internet Protocol, especially its implementation and efficiency. The thesis work is divided into three areas. The first area includes the development and implementation of a Management Information Base for the Mobile-IP protocol. The second area deals with the porting of a Mobile-IP implementation for SunOS to MachOS and Solaris. The last area covers the tests done to measure the throughput and latency of the protocol.

This thesis studies the SPACE method by creating building blocks for a Push to Talk (PTT)service in WLAN environment. The structure and behavior of a PTT service is analyzed anddiscussed. We have modeled the behavior of a PTT service with the GUI of the PTT client.As a result, several of building blocks for a PTT service have been proposed. They can bestored in a library for a later reuse. We consider that the SPACE method well suited fordeveloping a PTT service. / Denna avhandling studerar SPACE metoden genom att skapa byggstenar för en PTT-tjänst iWLAN miljö. Struktur och beteende för en PTT-tjänst analyseras och diskuteras. Vi harutformat en model för beteendet av en PTT-tjänst med GUI av PTT klient. Som ett resultathar flera byggstenar för en PTT-tjänst föreslagits. Vi anser att SPACE metoden är väl lämpadför att utveckla ett PTT-tjänst.

In addition to the problems that may occur in the Internet, the people who test mobile internet services confront additional challenges due to the wireless environment. If something goes wrong, it is very problematic for a tester to determine exactly where the error occurred and the reason why it occurred. Is it the software in the telephone that does not work properly, is the GPRS link stable, is the core network of the Internet working as it should, or is there something wrong at the server? The staff at Sony Ericsson has major difficulties determining where the origin of a problem is. They often simply know that something is not working. The major effort is often to detect the source of the actual problem rather than solving it. The PlayNow service provided by Sony Ericsson will be used as a reference service in this master’s thesis project. The PlayNow service is currently used for distributing ring signals. It is built on Internet standards, but depends on GSM’s specific features both for distribution and for e-commerce which makes it hard to test using existing web test tools. This Master’s Thesis examines the difficulties in establishing robust IP traffic links between a server and a mobile telephone. It examines the entire communication path between the mobile telephone and the server, and focus on how to detect (potential) errors. Within this project, development of a test tool is included. It supports features necessary for testing the reference service PlayNow. This report covers many different technologies within the mobile internet such as GSM, GPRS, and mobile IP. Moreover, the normal infrastructure of the Internet will also be considered; as well as how the different parts interact in an environment consisting of a mobile Internet with GPRS. A major part of the project has been evaluation of the communication link between a mobile device and a server. Additionally, some efforts have focused on developing the new test tool. / Utöver de problem som kan uppstå på Internet, konfronteras testare av mobila tjänster av ytterligare utmaningar på grund av den trådlösa miljön. Går något fel kan det vara väldigt svårt att lokalisera var problemet har uppstått och anledningen till varför det uppkom. Är det mjukvaran i telefonen som inte fungerar, är GPRS anslutningen stabil, fungerar kommunikationen över Internet som det ska, eller är det något fel med applikationsservern? De anställda på Sony Ericsson har många gånger stora problem att definiera vad källan till ett problem är. Ofta vet de bara att något är fel. Den stora mödan är ofta att hitta källan till problemet snarare än att lösa det. Tjänsten PlayNow som tillhandahålls av Sony Ericsson är referenstjänst för detta arbete. För närvarande används PlayNow för distribuering av ringsignaler. Tjänsten bygger på Internetstandards, men är även beroende av GSM specifika delar för både distribution och e-handel, vilket gör det svårt att testa denna tjänst med vanliga testverktyg för webben. I detta examensarbete undersöks svårigheterna med att etablera robust IP trafik mellan en mobiltelefon och en server och fokuserar på hur potentiella fel kan upptäckas. Inom ramen för detta arbete har ett testverktyg utvecklats. Detta verktyg tillhandahåller funktionalitet för att testa referenstjänsten PlayNow. Denna rapport behandlar många olika teknologier inom mobilt Internet, såsom GSM, GPRS och Mobil IP. Utöver detta har den vanliga Internet teknologin behandlas. Så som de andra delarna som är inkluderade i mobilt Internet med GPRS. En större del av arbetet har varit utvärdering av kommunikationsvägen mellan klient och server. Utöver detta har en del ansträngning lagts på att utveckla det nya testverktyget. Denna rapport visar på de svårigheter i att hitta källan till ett problem i kommunikationsvägen, vilka kan vara mycket svåra att hitta. För att göra felsökning enklare har ett testverktyg utvecklats. Med hjälp av detta nyutvecklade testverktyg, många brister i konfigurationen av PlayNow servern har blivit upptäckta och tillrättade.

Today large publishers are developing platforms via which their content, such as magazines, books, and newspapers, are distributed based upon the well established pattern of 'pay-per-content', via a multitude of mobile applications. Despite of the recent flourishing market of subscription possibilities, users currently have to buy single items of content at an average expenditure that is approximately equal to the cost of the printed media, because publishers are still investing in printing hardcover versions of their publications. Furthermore currently digital documents are mainly "scanned" versions of the printed ones, an unattractive format which does not exploit the potential of digital publishing. This format is rendered by the device in a way that does not permit the user to take real advantages of a digital environment, making the e-reading experience something that has no real added values, compared to regular printed publications. In order to provide to people an improved experience in terms of both accessing and enjoying their favorite material, the Leaf project aims to create a platform in which both publishers and readers can take advantage of an innovative business model and advanced technological solutions. As part of the Leaf project, the main objective in this subproject is the realization of a client that can access a set of online contents and offer these to the reader, by streaming content rather than requiring that the complete object should be downloaded in order to be rendered by the device. The access to the material should follow modern security standards, including data encryption, in order to prevent unauthorized use of the content. Furthermore, the client should present the content in an innovative way and allow the development of a mobile platform that could be supported based upon advertising, with an approach based on using information about the user (i.e. favorite places or profile details)as well as content-based advertising. In addition to the client application, the development of this subproject includes the development of a series of server-side utilities for the uploading and elaboration of publications on the server infrastructure. The document first reviews e-reading systems, focusing on the ePub file definition and e-reading solutions currently in use. The report then describes the Android OS development environment. The document then explains the implementation for both client and server side applications, giving a detailed overview of the chosen strategies and of the applications' structure. Finally the report concludes with a list of the achieved goals, a discussion on the project's limitations and then an exploration on what is the future for this client application. / Idag utvecklar många utgivare plattformar vilkas innehåll, såsom tidningar, böcker och veckotidningar distribueras via ett flertal mobila applikationer enligt den väletablerade ”pay-per-content” modellen. Trots den blommande nya marknaden som ger möjligheten till prenumeration, fårkonsumenterna fortfarande köpa enstaka publiceringar som ungefär kostar lika mycket som de tryckta media. Detta för att utgivarna fortfarande investerar i den inbundna versionen av deras publikationer. Dessutom är de digitala dokumenten främst en “skannade” version av det tryckta, enoattraktiv format som inte utnyttjar det digitala formatets potentialitet. Denna formatutförs av enheter på ett sätt som inte tillåter användare ta fördel av digitala möjligheter. Därmed, jämfört med tryckt material, erhåller läsningsupplevelsen inte något mervärde. För att ge en bättre upplevelse, både när det gäller att få tillgång och att ”njuta” av ensfavorit material, Leaf projektet vill skapa en plattform i vilken båda utgivare och läsare kanta fördel av en innovativ businessmodell och avancerade tekniska lösningar. Huvudmålet i detta delprojekt, som tillhör huvudprojektet Leaf, är realisering av en clientapplikation som har tillgång till online material. Detta material erbjuds till läsaren via streaming istället för att hela nedladdningen ska ske innan kundsenheten ska kunna börjaanvända det. Tillgången till materialet ska ske enligt moderna säkerhetsstandarder, datakryptering inbegripen, för att undvika otillåten användning av detta material. Dessutom ska client applikationen presentera innehållet på ett innovativ sätt och tillåtautvecklingen av en mobil plattform som ska kunna stödjas utav reklam. Tillvägagångssättet för att genomföra reklam ska baseras på användningen av information om användaren (till exempel favorita platser eller profildetaljer) likväl sominnehållbaserad reklam. Förutom client applikationen inkluderar detta projekt också utvecklingen av en serieserver-side verktyg för uppladdningen och utarbetandet av publikationer på serverns infrastruktur. Denna rapport ger först en recension av e-reading system, med fokus på ePub file definition samt e-reading lösningar som i dagsläget är använda. Efteråt förklararrapporten implementationen för både client och server side applikationer genom att ge endetaljerad översikt av de valda strategierna samt applikationernas struktur. Slutligen avslutas rapporten med en lista över de mål som har nåtts, en diskussion om projektets begränsningar och en prospektering på denna client applikationens framtid.

Value-Added Services and Content Platforms (VAS and Content platforms) was carried out with in a group with same name at Tele2 AB in Kista, Stockholm. This group is responsible for network design, capacity planning, dimensioning, Acceptance testing (ATP test), and introducing of new functionality in Tele2's VASplatforms. Acceptance testing is performed on new devices (servers and other network components) in order to verify their capacity and performance guaranteed by their manufactures. Every platform has a guaranteed upper bound performance (based on the license a buyer has paid for), measured by different approaches. For instance for Short Message Service Center (SMSC) platforms, the measurement is based on the maximum number of SMS messages processed per second (SMS/sec), for Multimedia Messaging Service Center (MMSC) platforms the metric is the maximum number of MMS messages processed per second (MMS/sec), and for WAP Gateways it is the maximum number of WAP Transactions Per Second (TPS). This M.Sc. thesis project involved creating two graphical load generators for load testing of SMSC and MMSC platforms. These application-programs are not allowed to occupy unnecessary resources, or cause additional traffic on the radio network (when they are deployed), but they must be powerful enough in order to send and receive traffic in order to derive statistical data about the system's performance. This data will be used for behavioral analysis of these systems, and finally for verifying the guaranteed capacities. These tests are very important and decisive for service providers, who want to be able to offer good quality of service, guarantee availability, and offer reliability. In order to measure the performance and verify the guaranteed performance, two main scenarios were of great importance: Sending 5 messages per second during a interval of 5 minutes. This case will simulate a TV-contest in which the TV audiences submit messages to a predefined number in order to join the contest. Sending 3 Multimedia Messages per second during 30 minutes (for the MMSC performance measurement), and 7 SMS-messages per second during 120 minutes (for the SMSC performance measurement). This case attempts to simulate the traffic that will be generated in the minutes before and after Christmas or New Year. For behavioral analysis and performance measurement of the MMSC and the SMSC platforms an Open Queueing Network model is employed. In this model each server system is considered as a network, consisting of nodes, where each node represents one component inside the system. By considering each node as a single-server queueing system we can take advantage of queueing theory in order to drive several performance results.

The Extensible Markup Language (XML) becomes more and more widespread as nearly all major players on the market today have accepted XML as an industry standard for exchanging information between server based products. Thus thousands of XML dialects have emerged since XML 1.0 became a W3C recommendation in February 1998. Corus Technologies AB has developed a server-based product called Corus/ALS© (Application Linking System) that makes it possible to connect client systems with different data representations to each other. A relational database model for each of the client systems is created and the translation from one data representation to another is done with stored procedures in the database. This thesis introduces a solution for how to store and retrieve XML documents in a Relational Database Management System (RDBMS) from any of the XML dialects that has emerged since XML 1.0 became a W3C recommendation. After a XML document has been stored in the database in a normalized way, the stored procedures in the Corus/ALS© database can be used to transform it to another XML dialect (or another format supported by the Corus/ALS© system). This will make it possible to translate any XML document to any other XML format. An XML interpreter was implemented and this implementation verified the theories in this thesis.