Mobile payments are increasing in popularity in recent years. New mobile solutions are being developed in the form of new Internet capable mobile devices such as the IPhone and new wireless networks such as the LTE and WiMAX networks. This report will present, explain and compare some of the most popular wireless networks that enable mobile payments, from a security point of view. The chosen networks are 3G with connection to GSM, and WLAN networks. The main security mechanisms involved in each network, and how they work will be studied. Security requirements and some of the most important threats each network faces will be presented and discussed. The main purpose of the report is to examine if mobile payments offer an acceptable level of security to the average user.

For a long time radio devices have been constructed in hardware with a fixed functionality. This way of constructing radio devices is starting to change with the concept of Software Defined Radio (SDR) evolving. The SDR concept leads to more flexible and long lasting radio devices. In order to make the radio software more standardized and portable, the U.S. military has defined the Software Communication Architecture (SCA). Internal communication within the SCA is done by CORBA, which limit waveforms to be only distributed over CORBA-capable hardware. The U.S. military has defined the Modem Hardware Abstraction Layer(MHAL) to enable distribution over devices not supporting CORBA. This thesis presents an implementation of MHAL and an underlying transport mechanism based on Ethernet. The implementation is done for the OSSIE package. The implementation is evaluated both in terms of real-time and throughput performance. The results show that MHAL achieves good performance, in comparison to CORBA, and can greatly be used to distribute waveforms over both CORBA and non-CORBA capable devices.

Long Term Evolution (LTE) is becoming the first choice of operators when constructingthe new network infrastructure, because of its high throughput and lowlatency. Although the LTE can offer high speed data service as a benefit of widebandapplication, the large bandwidth also results in huge control signaling cost.This thesis studies how the available radio resources should be allocated todifferent users for the particular purpose. Three proposals are presented in thisthesis. The first two aim at maximizing the overall net capacity. The factors ofchannel conditions and control signaling cost are considered in the first proposalwhereas power control is supplemented as an additional factor in the second one.The third proposal aims at achieving a tradeoff between subframe efficiency andaverage data rate. Channel conditions and control signaling cost are taken intoconsideration.Resource blocks scheduling under a control signaling cost constraint is feasiblewith the knowledge of the channel condition of users. This is obtained from channelstate information directly. The first proposal studies how this scheduling isdone. The second proposal takes power allocation scheme into account. In termsof computational complexity, the methods of internal water-filling and externalwater-filling are described in the second proposal. The simulation results illustratethat the net capacity in the first proposal can be enhanced by about 5% -60% in the second proposal. The exact percentage of increase depends on differentcontrol signaling penalty.The third proposal discusses how to implement flexible subframe length underthe Rayleigh fading channel condition in the LTE system. The objective is toachieve subframe efficiency as high as possible, while maintaining the maximumaverage data rate. The simulation results illustrate that the optimal subframelength depends on control signaling cost penalty as well as on Doppler frequency.Finally, the fairness of the first proposal is compared with the improved versionsof Round Robin, Dynamic Allocation and Proportional Fair scheduling algorithms.The simulation results show that Round Robin and Dynamic Allocationoutperform the first proposal under a certain condition. / LOLA (Achieving Low Latency in Wireless Communication) is funded by EU FP7 (European Community’s Seventh Framework Programme).

This master thesis investigates the uplink transmition from User Equipment (UE) to base station in LET (Long Term Evolution) and channel estimation using pilot symbols with parameter defined in 3GPP (3rd Generation Partnership Project) specifications. The purpose of the thesis was to implement a simulator which can generate uplink signal as it is generated by UE. The Third Generation (3G) mobile system was given the name LTE. This thesis focus on the uplink of LTE where single carrier frequency division multiple access (SC-FDMA) is utilized as a multiple access technique. The advantage over the orthogonal frequency division multiple access (OFDMA), which is used in downlink is to get better peak power characteristics. Because in uplink communication better peak power characteristic is necessary for better power efficiency in mobile terminals. To access the performance of uplink transmition realistic channel model for wireless communication system is essential. Channel models used are proposed by International Telecommunication Union (ITU) and the correct knowledge of these models is important for testing, optimization and performance improvements of signal processing algorithms. The channel estimation techniques used are Least Square (LS) and Least Minimum Mean Square Error (LMMSE) for different channel models. Performance of these algorithms has been measured in term of Bit Error Rate (BER) and Signal to Noise Ratio (SNR).

No description available.

This paper is a study of IEEE Standard 802.16 Medium Access Control (MAC) Layer in Distributed Mesh Networks. IEEE Standard 802.16 is a Wireless Metropolitan Area Network (WMAN) technology that can connect different IEEE 802.11 (Wifi) host post with each other and to other parts of internet. It can provide network for a wireless router and at the same time this router can be installed in the office, house or university. WiMAX (Worldwide Interoperability for Microwave Access) is a certification mark for products that pass conformity and interoperability tests for the IEEE 802.16 standards. Products that pass the conformity tests for WiMAX are capable of forming wireless connections between them to permit the carrying of internet packet data. The idea of WiMAX is similar than Wi-Fi but it is not the same. It is a step much higher than Wi-Fi because it is focused to offer internet for a whole city. It has much higher capacity and longer distances. IEEE 802.16 defines a MAC Layer that supports multiple physical layer (PHY) Specifications and different topologies; Point to Multipoint (PMP) and Mesh Networks. In this first topology there exist a Base Station (BS) that have direct links with all the Subscriber Stations (SS). If any Subscriber Station requires transmitting to another SS, the message must convey the Base Station.

The trends in todays tele- and datacommunication market point toward using IP for all sorts of service delivery ranging from voice calls to TV. The next natural step in this evolution is to provide the same set of services to the end users independent of the access technology and device used. The IP Multimedia Subsystem (IMS) is an IP based telecommunications platform which targets this and lets the operators develop new services once which can then be used on many different devices. This thesis examines the integration of IPTV and IMS. Can IMS be used to deliver TV services and can the IPTV set-top-boxes of today be used as clients in IMS? Since this is a new and previously unexamined area an explorative approach is taken. The aim is to identify how such an integration could be performed and the possible problems which have to be solved. To assist in this exploration a TV-push service based on IMS technology is constructed. Based on the experiences from this service a general architecture for IPTV in IMS is suggested. A number of problems crucial to solve for a successful integration are identified and possible solutions to these are discussed.

<p>Due to the scarcity of wireless resources, efficient resource allocation is essential to the success of cellular systems. With the proliferation of bandwidth-hungry multimedia applications with diverse traffic characteristics and quality of service requirements, the resource management is becoming particularly challenging. In this thesis, we address some of the key link-layer resource allocation mechanisms that affect the performance of video streaming in cellular systems: bit-rate allocation, opportunistic scheduling, and statistical multiplexing. The bit-rate allocation problem involves the distortion-optimal assignment of source, channel, and pilot data rates under link capacity constraints. We derive an analytical model that captures the video distortion as a function of these data rates and, based on it, we study various bit-rate allocation strategies. The opportunistic scheduling problem addresses the throughput-optimal assignment of time-slots among users with diverse channel conditions under certain fairness constraints. We focus on two aspects of the opportunistic scheduling: the performance of delay-constrained streaming applications and possible extensions of the opportunistic concepts to multicast scenarios. Finally, the statistical multiplexing is a resource-efficient method for smoothing out the extreme burstiness of video streams. We study possible statistical multiplexing gains of H.264 video streams in the context of E-MBMS architecture.</p>

<p>The Internet has rapidly evolved from being a scientific experiment to a commercial network connecting millions of hosts that carries traffic generated by a large amount of applications with diverse requirements. Its architecture was however designed to enable efficient point-to-point delivery of bulk data, and can not provide statistical guarantees on the timely delivery of delay sensitive data such as streaming and real-time multimedia. Thus, applications that require low loss probabilities in today's Internet have to use some end-to-end error recovery mechanism. For delay sensitive applications the introduced latency by the applied schemes has to be low as well. Traffic control functions such as delay limited shaping and forward error correction (FEC), and multiple description coding (MDC) have been proposed for variable bitrate video. Their major drawback is, however, that it is difficult to predict their efficiency, as it depends on many factors like the characteristics of the stream itself, the characteristics of the traffic in the network and the network parameters. Consequently, it is difficult to decide which control mechanisms to employ, how to combine them and to choose the right parameters (e.g. block length, code rate) for optimal performance.</p><p>In this thesis we present results on the efficiency of traffic control functions and MDC for video transmission based on mathematical models and simulations. We investigate the efficiency of delay limited traffic shaping and the trade-offs in the joint use of traffic shaping and forward error correction. We identify the packet size distribution of the traffic in the network as an additional factor that may influence the efficiency of FEC, and present a thorough analysis of its possible effects. We present an analytical comparison of MDC versus media-dependent FEC and media-independent FEC, and based on the results we conclude that MDC is a promising error control solution for multimedia communications with very strict delay bounds in an environment with bursty losses. We combine the analytical results with traces from measurements performed on the Internet to evaluate how efficient these error control schemes are under real loss patterns. We compare the efficiency of MDC and media-dependent FEC in the presence of channel estimation errors; we propose a new rate allocation method, which is robust to mis-estimations of the channel state and which improves error resilience on non-stationary channels. Finally we present an analytical model of the performance of an end-point-based multimedia streaming architecture based on multiple distribution trees and forward error correction, and analyze the behavior of the architecture for a large number of nodes.</p>

<p>Secure networks require each node to individually be as secure as possible. Transporting telecommunication data using IP based networks increases the need for security solutions due to increased exposure to threats. Ericsson currently provides a reference solution for carrying radio traffic over standardized Ethernet using IP, which in the current version relies on third party equipment. This equipment, and their recommended configuration, needs to be tested to ensure that the reference solution is as secure as possible.</p><p>The main purpose of this thesis is to provide Ericsson with a template that describes how security testing of the currently recommended equipment can be carried out.</p> / <p>För att ett nätverk skall vara säkert krävs att dess noder är invidivuellt säkrade. Transportering av telekommunikation över IP baserade nätverk ökar behovet av säkerhetslösningar då det ökar riskerna. Ericsson erbjuder idag en referenslösning för transport av telekommunikationstrafik över IP nätverk, som i dagsläget använder tredje-parts-utrustning. Denna utrustning och den konfiguration som rekommenderas i referenslösningen behöver säkerhetstestas för att säkerställa att den erbjudna lösningen håller en hög säkerhetsnivå.</p><p>Huvudsyftet med detta exjobb är att ta fram en praktisk metod som kan användas vid Ericsson för att säkerhetstesta den utrustning som i dagsläget rekommenderas i referenslösningen.</p>