<p>This thesis focuses on the analysis of the rerouting times in UNINETT, the Norwegian research network. Rerouting happens in case of a topology change of the network, and the routers have to calculate new paths to all destinations. The downtimes due to rerouting is a major contributor to the overall service unavailability. Because of this it is of interest to study the different components of these downtimes, and propose changes to speed up the rerouting process. The main goal for the thesis is to improve the service availablility in UNINETT. In UNINETT there are measurements of periods of packet loss available. These measurements, as well as the statistics from the network nodes, are analysed and the results are presented in this thesis. UNINETT is a network with IS-IS as the routing protocol, and fault handling by path restoration. Fault handling by path restoration means there is no spare capacity to switch to in case of a link or node failure. All routers in the network have to be updated about the topology change, and find new paths around the failure. The delay to update the network nodes to a common stable view, is called the convergence time. During this period it is observed packet loss, and it is of interest to make this period as short as possible. The reason for the packet loss during the convergence time is the inconsistency in the router's routing and forwarding tables. The construction of transient loops between nodes can happen in this phase. This will impose extra load to the network, delay, and in worst case loss of packets. These loops are called micro loops and increase the downtime during the convergence period. The parametrization in IS-IS is studied, and changes to the parameter values are proposed. Too much tuning of the parameters may introduce instability in the network, which increase the load to the nodes and links. This can lead to even longer convergence time, and periods with packet loss. The recommended values are tested in a small test lab replicating parts of the topology of Northern Norway in UNINETT. The results from the test are compared with a case study of a failure on the Trondheim-Troms?? link in UNINETT. The observations from the case study show a typical delay of up to 10 s for the convergence time. The results from the test lab show that it is possible to achieve sub-second convergence time, without any compromise on the stability of the network. Due to the small scale of the test lab, the traffic intensity was too low to observe any overload to the nodes or links. This may be a problem in a full scale network like UNINETT, and further testing is recommended before the proposed changes to the parameters are implemented in any production network. The fault handling in UNINETT is also studied, which includes the contribution from the different components to the convergence time. The observations and results from the mentioned case study and test lab are used in this study too. It is observed that the timer delay before the "Shortest Path Tree" computation is run in the routers, is the major contributor to the convergence time. This is improved by tuning the SPT timers, as observed in the results from the test lab. The failure detection and flooding components are also large contributors to the convergence time. The test lab shows that the failure detection is improved by tuning the hello parameters in IS-IS, but a less processor intensive method called BFD is recommended for further study. The parameters triggering the data-link layer timers may also be a possibility to speed up the failure detection, but this is not further investigated in the thesis. The flooding component is reduced by enabling the fast flooding command. The phenomena of micro loops is studied, and the method called oFIB is recommended for implementation in UNINETT. Micro loops are a small contributor to the convergence time in UNINETT today, but the customers' requirements for service availability are increasing, and the necessity of a solution is in near future. In addition to the oFIB method, a fast repair technique like IPFRR may eliminate almost all downtimes during rerouting in UNINETT, but this is subjects for further studies.</p>

<p>Broadband connectivity has increased significantly the last years. More and more households choose to subscribe to services from various broadband companies. This has led to a range of new services. Some of these have high demands to both bandwidth and quality of service. Network operators have until recently neglected the challenges of providing network coverage within customer homes. Wireless solutions have been widely used, but new and demanding services like HDTV will either need a wired network or a significantly improved wireless standard. The complexity of in-home connectivity has increased dramatically because of a constant increasing number of devices and severe technical requirements. Convergence of earlier separated services is one of the main reasons for these new technical challenges. Different services with various demands are delivered over the same physical pipeline. The convergence of television, Internet and voice services, known as triple play, is delivered by both cable and fibre network operators today. Telecom operators are looking for ways to deliver triple play to compete in this new market. In addition to technical challenges, high costs and uncertain revenues slow down the development. In this thesis, we look at general technical requirements as well as business aspects regarding the development of a home network solution. Various technical solutions for in-home wiring are discussed. Because of high costs attended with installation of new wires in people's homes, usage of existing wiring is recommended. Power line technology (HomePlug) as well as data over coax and copper (HomePNA) are presented as actual solutions. Wireless LAN standards are mentioned and the new 802.11n standard is recommended as the next WLAN solution to be embedded in the future home network. The support of Ethernet is also recommended beacause it is well proven and delivers high bandwidth as well as low latency and jitter. The support for these various interfaces should be embedded in the Residential Gateway (RG) which is delivered by the network operator and resides in the transition between the access network and the home network. The RG is "the brain" in the home network and controls all services. One of the main tasks for the RG, is to deliver the appropriate Quality of Service (QoS) for the different services. This is done through a remote management system that ensures end-to-end QoS. The establishment of triple play leads to changes in existing business models. Telephone companies, broadcasters and cable network operators are among the involved actors. How to increase customers' value and how to ensure return on investment are central questions regarding the development of a triple play business model. Revenues must be ensured to get acceptance among stakeholders. A general business model for a network operator launching triple play is presented in the thesis. The model is based on a pre-defined business model ontology and uses elements from the involved actors' existing models. The establishment of the "connected home" which emphasize ease of use and personalization is central in the proposed value proposition. A home network user interface accessible from the various in-home devices is recommended to ensure customer control and user friendliness. Services like video on demand, personal video recording, interactive television and Internet should be accessible through the user interface. The network operator should differentiate from competitors by offering their customers a complete home network solution where ease of use, performance and personalization are emphasized. Partnerships with actors in the content and advertising industry as well as equipment manufacturers are discussed. To ensure low cost and high quality equipment as residential gateways and set top boxes, good partnerships with equipment manufacturers are essential. TV channels and independent content must be retrieved through partnerships with the copyright holders of the content. By making content available independent of TV-channels, network operators can take over parts of the television business which is operated by broadcasters and television programmers today. VoD and pay-per-view services will probably gradually take over for existing television services. Network operators have a golden opportunity to take over great shares of this business. Advertising can generate important revenues for network operators. The ability to personalize advertisements and offer shopping directly from the TV-set increases the value of advertising. Commercials can be displayed in the home network user interface and in connection with services as video on demand. Content with commercials attached can be offered at reduced price or for free, hence intercepting the customers with low willingness to pay. The financial aspects regarding home network solutions are discussed generally and with a low detailing level in this thesis. Huge costs are connected with the development of triple play and home network solutions, but there is also a high potential for revenue generating services and income from advertising and shopping. But, to generate any revenues, the network operator is dependent on customers. Hence, acquiring and retaining customers by delivering highly valued services and good customer support is the key to success.</p>

<p>Active Radio Frequency Identification (RFID) tags that comply with IEEE 802.11 standards are currently used within indoor Real-Time Location Systems (RTLS) in several niche markets. With the rapid deployment of citywide wireless networks, outdoor Location-Based Services (LBS) have become an important research area. Such services are believed to have a considerable business potential in citywide wireless networks. Wi-Fi RFID tags can be used to take advantage of such a potential. However, very limited testing has been carried out in order to examine the performance of the Wi-Fi RFID technology in outdoor environments. Wireless Trondheim is one of the first citywide wireless networks in Europe. In this Master's thesis, the possibilities for building commercial services based on Wi-Fi RFID tags in Wireless Trondheim are examined. Three potential services, which can utilize such tags are also proposed. In order to verify the reality of a possible implementation of these services, five test scenarios are carried out with Wi-Fi RFID tags within Wireless Trondheim. The location-based solution in Wireless Trondheim has explicitly no support for determining location in outdoor environments. Nevertheless, testing is important to identify how well the Wi-Fi RFID technology perform in such environments. The results presented in this report point out several limitations with this technology in the citywide wireless network. Considerable variations in the location accuracy and precision are revealed. Problems with delayed location updates when traveling between adjacent coverage zones are also discovered. These limitations constrain the commercial services that can be based on Wi-Fi RFID tags in Wireless Trondheim. Currently, on-demand services with limited requirements to the accuracy of the computed location are supported to some extent. However, real-time services, which require a high degree of location accuracy are not supported with the location-based solution in this citywide wireless network. The described limitations should be improved in order to achieve an acceptable performance for LBS. Such improvements are also essential in order to determine the business potential of LBS in in a citywide wireless network like Wireless Trondheim.</p>

<p>This report starts out discussing a framework for building an API monitoring system. In such a system, malicious code can be run, and its actions can be taken notice of. I look into different analysis tools for stuctural analysis, and API monitoring tools. I will also discuss dynamic analysis using a debugger, and anti-debugging techniques used by modern malware. When using a debugger, API hooking can be implemented using brakepoints as well. In any case, we will need an isolated environment. The best candidate for this is virtual machines. I will look at different ways of controlling a virtual guest from a host system. On VMware, we can use both normal networking interfaces, and a backdoor, which is really an i/o port. I will also look into techniques for detecting virtual machines, and some counter-techniques. Packing mechanisms and ways to undo them is central to malware analysis. In this paper I have unpacked and analysed several samples of the Storm Bot, which is packed using UPX. Additionally, the APIs used by Storm has been determined. Dynamic analysis can be based on API usage. Scripting VMware is a central part of the last chapter. I will demonstrate several ways of doing this. It seems this can be a good foundation for building automated analysis solutions. I will also discuss the PaiMei framework which integrates the most useful analysis tools, and can work as a framework for building programs that automate the process of malware analysis. A report on malware analysis would not be complete without viral code. Cermalus is a recently released virus, which assembly source code has been included in the appendix. The source is well commented, and clearly states what the different routines are used for. You will find many of the terms used in these comments explained throughout this report.</p>

<p>Traditional routing protocols build routing tables that are optimized on one parameter only, this parameter is typically hop counts. With the introduction of new requirements, brought forth by a wide range of communication intensive, real-time multimedia applications, more sophisticated routing techniques are required. However, computing routes subject to different requirements and in environments with changing traffic patterns and network topologies, is often computationally excessive and the problems are frequently NP hard. Swarm based algorithms, inspired by the foraging behavior of ants are candidates to solve such routing problems. To ensure system robustness and scalability, routing should be truly distributed and adaptive. The ac{CEAS} is an adaptive, robust and distributed routing and management system based on swarm intelligence. CEAS is performing stochastic routing with fast restoration on link failures. Previous work has shown that CEAS is robust and efficient in solving complex optimization problems such as finding primary and backup paths or simple cyclic paths (p-cycles) in networks. In all swarm systems there is a tradeoff between performance and management overhead (number of management packets). The focus in this work is on reducing the overhead in terms of management packets generated in ac{CEAS}. To achieve this, a new algorithm is proposed that applies pheromone sharing between sources going to identical destinations. Performance results from simulations show that the new CEAS system presented in this report outperforms the original CEAS in most scenarios.</p>

<p>The IP Multimedia Subsystem (IMS) is intended by the Telco industry, to make it easy for third-party application developers to create new, innovative services that will help to offset the fall in revenue of regular voice services. However, a slow roll out of the system is increasing the chance of a disruptive technology to fill some of the space that IMS hopes to cover. This thesis presents a hands on example of the implementation of such a new innovative service. XMPP has been used as an alternative platform to launch the service, and is thoroughly compared to the IMS in this master's thesis. Ironically the service could not be launched on IMS due to technical problems. Results suggest that XMPP could replace IMS as a service platform, thus disrupting the business model of IMS.</p>

<p>The number of different identities and credentials used for authentication towards services on the Internet has increased beyond the manageable. Still, the most common authentication scheme is based on usernames and passwords which are neither secure nor user-friendly. Hence, better solutions for simplified, yet secure authentication, is required in the future. This thesis present an authentication scheme based on a One-Time Password (OTP) MIDlet running on a mobile phone for unified authentication towards any type of service on the Internet. The scheme is described in detail by an analysis and a design model. Based on the analysis and design an implementation of a prototype has been developed using Java. The security aspects of scheme are thoroughly evaluated in a security evaluation which identifies threats, security objectives and possible attacks. The proposed solution offers a strong authentication scheme which can substitute many of the authentication schemes we are using to day. Not only can it replace the standard username/password scheme, but due to its security services it can also replace stronger schemes such as existing OTP and smartcard solutions. Therefore the solution is suitable for many services on the Internet which requires authentication such as Internet banking, corporate intranet, Internet stores and e-Government applications.</p>

<p>The extensive list of cultural offerings in big European cities has resulted in a variety of city guides in magazines and on the Internet. However, users often require information when they are on the run. A city guide available on mobile phones would therefore be advantageous in many situations. In January 2007, the company CityMob was founded by four students in order to commercialise the idea of a city guide for mobile phones. A working prototype of the system has been designed and implemented. The prototype consists of a J2ME client, which is installable on mobile phones, and communication with an internet server using the mobile data access networks. Furthermore, business aspects related to the idea has been investigated and market research has been carried out. A business plan, which is based on the findings, has been formulated. Based on contributions from the prototype and the business plan, CityMob has obtained grants of, in all, 135 000 NOK. Moreover, a collaboration with the Munich located city magazine, Munichx, has been established. On this basis, a foundation for a viable company has been laid. CityMob will, in collaboration with Munichx, launch a final version of the mobile city guide on the German market 22 September 2007. After the scope of this thesis, several items are left to be resolved before the service is ready for market launch. Firstly, device portability and content provider scalability has not been emphasized while developing the prototype. Secondly, CityMob must enter into additional collaborations in order to provide a complete system.</p>

<p>Efficient solutions for Web Services on mobile devices would allow truly global, platform independent and interoperable information access, anywhere and at any time. While Web Services are continuously gaining ground, they are commonly reserved for use on personal computers and high-capacity servers, even though mobile devices are continuously becoming more advanced in terms of processing resources and wireless communication capabilities. This thesis identifies several challenges of accessing Web Services from mobile devices, and evaluates and discusses methods for creating more efficient solutions. Some of the challenges are the limited bandwidth and high communication latency. Reducing the size of XML information transferred and optimizing the communication protocol stack are identified as possible solutions to overcome these challenges. Additionally, as the communication cost correlates with the amount of data transferred, more efficient Web Services solutions are clearly beneficial for the end-user. The approaches described to reduce the size of XML files are traditional compression, alternative representation of the files, and binary XML. Binary XML is a compact representation of information that keeps the desirable structure of XML intact. The Efficient XML Interchange format currently being standardized by W3C is studied in more detail. Furthermore, optimizing the protocol stack has also been evaluated. A prototype Web Service system has been developed and tested in both simulated environments and in real surroundings using GPRS, EDGE and UMTS network connections. The results from the measurements show that both compression and the use of binary XML reduce the size of the information significantly and thereby the cost. Time needed to transfer the information is also reduced, and this effect is most apparent when the original files are large. Binary XML may however be the desirable format since it enables direct interaction with the information and keeps the memory footprint small. To reduce the time needed to transfer the information further, removing the HTTP protocol and optimizing the transport protocol, seems to minimize the effect of the latency.</p>

<p>In the later years, fault tolerant distributed systems have been applied to a variety of network internal and external services. Keeping distributed systems consistent and fault tolerant require management functionality. Jgroup/ARM is a java based prototype system which automates this management functionality for fault tolerant distributed systems. This thesis presents an evaluation of the dependability characteristics of the Jgroup/ARM system. Both static and dynamic modelling techniques are introduced, but the main focus is on the dynamic techniques; state-diagrams and Petri net models. Previous work is evaluated to nd an approach suitable for dependability modelling of Jgroup/ARM. A system delivery model for Jgroup/ARM is developed based on its functionality. The monitored subsystem is dened to include the hardware (processors), a given number of services in the system and the replication management functionality (ARM framework). A Petri net model of Jgroup/ARM is developed in the Möbius modelling tool based on the system delivery model. A model of a single service replicated on a cluster of processors is developed, analyzed and expanded to include multiple services and the ARM framework functionality. The dependability of Jgroup/ARM is evaluated through simulating example scenarios in Möbius. The results show that the system availability is very high, even with a relatively high failure rate.</p>