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  • 301.
    Holmlund, Erik
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    A comparative study of two different network basedIP Virtual Private Network solutions2003Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Network based (layer 3) IP VPNs is a growing service and Skanova has a solution today which has received a lot of customer attention. The service is called VPN Flex and offers the customers secure communication between their different offices while supporting different traffic classes with a guaranteed maximum delay, jitter, and packet loss. VPN Flex has been a success so far in terms of the number of customers that have signed up for it in the short time it has been on the market. VPN Flex is realized over an IP network on Skanova's ATM backbone.

    Meanwhile Multi Protocol Label Switching (MPLS) has attracted a lot of attention and is considered to have a lot of nice features; the most import being the ability to provide layer 2 and layer 3 IP VPNs. The MPLS solution for providing network based layer 3 IP VPNs is described in RFC 2547, also called BGP/MPLS VPNs. It has become the de-facto standard for providing network based layer 3 IP VPNs. Skanova's VPN Flex service is provided by a partly Nortel proprietary solution using IP tunneling instead of MPLS tunneling which is used in RFC 2547.

    The purpose of this paper is to evaluate which network (i.e. link layer technology; specifically a frame based or a cell based media) and which network based IP VPN solution is most suitable to provide a network based layer 3 IP VPN service that supports different traffic classes so that Skanova's customers can use this VPN service to send best effort traffic, mission critical applications, IP Telephony, and Video Conferencing services between their different offices using a single layer 3 VPN solution.

    In my evaluation I have looked at the technology behind the VPN solution, the ability to provide delay, jitter, and packet loss guarantees as well as what it costs to produce the service along with the security and expected reliability. The purpose of having a master’s thesis student looking at this problem is that I would be objective and not have any predetermined conclusions.

    The result of the study is that the two different network based VPN solutions are not different with regard to the service they provide for the customers. However, there are some differences that affect the operator deploying and running the service. RFC 2547 is a more flexible solution with less manual configuration and better support for Inter-AS VPNs. It is possible to realize an RFC 2547 solution in either an ATM network or an IP network and the services will be implemented in much the same way. Both solutions could use Label Distribution Protocol (LDP) signaling and EXP Inferred PHB Scheduling Class LSPs (ELSPs), realizing traffic classes using the MPLS EXP bits. Which network to base the solution on, is a matter of QoS support, costs, and security. The ATM network today has better QoS support (such as more transmission queues and efficient schedulers). However, at the link speeds used in today’s backbones the fixed size cell of ATM is not a reason to use the ATM network instead of a frame based IP network.

    The cost of using Packet Over Sonet (POS) and ATM is the same. However, using Ethernet the port cost is less than half of either POS or ATM, which favors using an IP network in the A comparative study of two different network based IP Virtual Private Network solutions future. The security of a network based layer 3 IP VPN is mostly in the hands of the operator configuring the service and the network. Thus with regard to security, I do not believe there is a difference when realizing the network based IP VPN service in a public or private IP network. However, a network based IP VPN realized in a public IP network might pose a sales problem because many customers are worried about the security and availability of such a network.

    RFC 2547 and MPLS seem to be the way to go in the future, but my recommendation is to make the transition slowly thereby minimizing Capital Expenditures (CAPEX). This is especially true since the current network based IP VPN service has been so well received. Whether Skanova should introduce MPLS and RFC 2547 in the IP network or the ATM network is very much dependent on their future strategy. I believe that both the IP network and the ATM network can support a service such as VPN Flex. Also, the way that MPLS will be used with regard to the VPN Flex service is the same.

  • 302.
    Holmstedt, Christoffer
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Model-checked Space Plug-and-Play Architecture Local Subnet Adaptation implemented in Ada with Ravenscar restrictions2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Space Plug-and-Play Architecture (SPA) is a set of standards to make it easier to build small satellites. Focus is put on improving the integration phase andthe time consuming validation and verification process by introducing plug-and-play functionality. From mission call-up to operational satellite it should only take six days.

    A SPA network consists of several different types of subnets with differentpros and cons. For each processing node there must be one Local Subnet Manager (SM-L). The SM-L can communicate over different communication protocols depending on how the respective local subnet is set up, one option is UDP/IP.

    In this thesis Ada Protected Objects is presented as a viable option for inter-process communication instead of UDP/IP in a SPA network. This thesis presents the initial work towards a SPA Local Subnet Adaptation that builds onlanguage constructs in Ada such as Ada Tasks and Protected Objects. The system design and implementation is verified deadlock free with UPPAAL but showsindications of livelock possibilities. The severity of these livelocksituations is discussed in the conclusion.

  • 303.
    Holmsten, Maria
    KTH, Tidigare Institutioner, Teleinformatik.
    Mobile IP: Mobile communication for a mobile user1999Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In a near future, computer users will want to be able to move around in a network and to log on to the nearest computer. Users will want to work and interact in an environment according to their own preferences, just as in their home network. This thesis proposes an extension of the terminal mobility supported by mobile IP [6] with user mobility support.

    The theoretical background in the thesis focuses on, after distinguishing between different types of mobility to: (1) present Mobile IP, (2) introduce user mobility and also to discuss some requirements, and (3) give a general description of agents.

    It is suggested that a User Agent (UA) represents a single user in the network and is responsible for his/her mobility. A user is registered at zero or more IP nodes. In order to allow several users to share the same IP node, a Remote User Agent (RUA) is required for each user on his/her IP node. The RUA will be created remotely at the specific mobile node, by the user’s UA.

    A User Profile contains information and preferences related to a user. Also, through its profile, the owner of a terminal can protect it from being at registered by other users. The UA has a User Registration Container which is composed of a User Profile and a User Registration Table, containing information about each of the user’s current registrations.

    A user registers at a mobile node through a User Registration Interface which is accessed through a Web browser after the necessary identification and authentication procedures have been completed.

  • 304.
    Hossain, Md. Iqbal
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Hossain, Md. Iqbal
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Dynamic scaling of a web-based application in a Cloud Architecture2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    With the constant growth of internet applications, such as social networks, online media, various online communities, and mobile applications, website user traffic has grown, is very dynamic, and is oftentimes unpredictable. These unpredictable natures of the traffic have led to many new and unique challenges which must be addressed by solution architects, application developers, and technology researchers. All of these actors must continually innovate to create new attractive application and new system architectures to support the users of these new applications. In addition, increased traffic increases the demands for resources, while users demand even faster response times, despite the ever-growing datasets underlying many of these new applications. Several concepts and best practices have been introduced to build highly scalable applications by exploiting cloud computing. As no one who expect to be or remain a leader in business today can afford to ignore cloud computing.

    Cloud computing has emerged as a platform upon which innovation, flexibility, availability, and faster time-to-market can be supported by new small and medium sized enterprises. Cloud computing is enabling these businesses to create massively scalable applications, some of which handle tens of millions of active users daily. This thesis concerns the design, implementation, demonstration, and evaluation of a highly scalable cloud based architectures designed for high performance and rapid evolution for new businesses, such as Ifoodbag AB, in order to meet the requirement for their web based application. This thesis examines how to scale resources both up and down dynamically, since there is no reason to allocate more or less resources than actually needed. Apart from implementing and testing the proposed design, this thesis presents several guidelines, best practices and recommendations for optimizing auto scaling process including cost analysis. Test results and analysis presented in this thesis, clearly shows the proposed architecture model is strongly capable of supporting high demand applications, provides greater flexibility and enables rapid market share growth for new businesses, without their need to investing in an expensive infrastructure.

  • 305.
    Huang, Liang
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    On-line storage versus local storage for mobile users2006Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    When a user has a mobile device with lots of built-in functions, what would they like to do with it? Of course, interactive voice and videoconferencing, sending SMS & Instant Messaging, listening to music, taking photos, etc. People want to have a device with a large storage capacity, much as they do on a desktop or laptop PC. But sometimes the user does not have sufficient local storage capacity on their mobile device. Online storage is a good solution for this, but the limited battery capacity connectivity must be balanced such require that the mobile decided what should be uploaded/downloaded and when - along with what should be stored locally.

    This problem is very significant not only theoretically, but also practically. We expect that the online storage will replace storage media, such as CDs and DVDs. Today use of a mobile device is a very popular. Users would like to be able to easily send files to friends in other parts of the work, and share files with these friends. Additionally, users to not want to loose important data (photos, files, ... ), these functions can all be implemented using on-line storage. Use on-line storage should be simpler for the user, thus smart mobile devices should simplify the user’s experience, provide safer file storage (i.e., with a lower risk of data loss), and to store files in the most appropriate location(s).

  • 306.
    Hult, Yngve
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för informatik och media.
    Montgomery, Patrik
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för informatik och media.
    Övergången från IPv4 till IPv6: En fallstudie om faktorer som påverkar övergångens hastighet.2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Today the internet is a world wide web connecting billions of devices. All these devices need an IP-address to be able to communicate with one another. With the current version of the internet protocol, IPv4, the address space is limited. To solve this problem a transition to the latest version, IPv6, has begun. But the transition is going slowly partly because of a temporary solution called NAT, Network Addressing Translation. With the help of interviews with highly appointed employees from large IT companies in Sweden, this study examines the impact of factors other than NAT that are affecting the speed of the transition, and why a technically advanced country like Sweden is so far behind in this process. The results show that the demand of the consumers is not high enough and that cost versus incentives is not balanced well enough for a transition to go quicker. But in time the speed will increase and further research could perhaps help the speed of the transition grow.

  • 307.
    Hutter, Jonas
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    Mashayeke, Mehnaz
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska högskolan.
    A dynamic decision model and a system logic evaluation for Sandvik Machining Solutions distribution flows2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The aim of this thesis is partly to create a dynamic decision model for Sandvik Machining Solutions distribution flows and partly to evaluate how the stock transfer system logic handle four specific exceptional situations. The purpose is to reduce the total costs while keeping or improving the service level. The thesis presents a total cost model and guidelines for the planning function when deciding the main supplier in the distribution. The thesis also presents a system logic evaluation of the stock transfer logic used by Sandvik Machining Solutions.

  • 308.
    Hägglund, Andreas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Geo-process lookup management2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis presents a method to deploy and lookup applications and devices based on a geographical location. The proposed solution is a combination of two existing technologies, where the first one is a geocode system to encode latitude and longitude coordinates, and the second one is a Distributed Hash Table (DHT) where values are stored and accessed with a $<$key,value$>$ pair. The purpose of this work is to be able to search a specific location for the closest device that solves the user needs, such as finding an Internet of Things (IoT) device. The thesis covers a method for searching by iterating key-value pairs in the DHT and expanding the area to find the devices further away. The search is performed using two main algorithm implementations LayerExpand and SpiralBoxExpand, to scan the area around where the user started the search. LayerExpand and SpiralBoxExpand are tested and evaluated in comparison to each other. The comparison results are presented in the form of plots where both of the functions are shown together. The function analysis results show how the size of the DHT, the number of users, and size of the search area affects the performance of the searches.

  • 309.
    Hällström, Magnus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Operativsystem   för småföretag, en studie av Windows 82012Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Den här uppsatsen handlar om Windows 8 och hur dess funktioner kan förbättra arbetet för ett litet företag. Hur kommer Windows 8´s nya applikationshantering att påverka arbetet?

  • 310.
    Hällström, Magnus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Strömmande video i trådlösa mesh nätverk: Streaming video in wireless mesh networks2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This document’s content is the final report of the master´s dissertation Magnus Hällström did during springtime of year 2013. The dissertation’s subject is 802.11s wireless mesh networks with streaming video as a focus point.  During the dissertation a wireless mesh network was set up with different attached cameras for streaming video. A sun panel solution was also tested with the goal of creating a package with a self-configuring network node streaming video, powered by nothing but solar energy. 

  • 311.
    Hådén, Thor
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    IPv6 Home Automation2009Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Home automation is the systematic controlling and monitoring of everyday home devices such as lighting, heating, window blinds and appliances (both white goods and home electronics). This report describes how to control and monitor home appliances over IPv6 by using existing home automation hardware and an Internet connected gateway.

    There are many commercial home automation systems available. However, these are often proprietary and/or designed for limited use. This project seeks to pave the way for IP-enabling home appliances, making such devices part of the Internet. Therefore, these devices can individually be controlled both from within the home and remotely. Internet enabling each of these devices eliminates the need for special Internet connected control units, simplifying home automation and hopefully giving yet another incentive to deploy IPv6 on a larger scale. The practical goal of this project has been to create a virtual, but practically usable, IPv6 home automation system. This has been done using existing simple home automation hardware tied to a gateway relaying uniquely addressed IPv6 command messages to the appropriate device. This gateway's only function will be to translate IPv6 commands to whatever interface the device being controlled is using (this includes translating to and from the appropriate link and physical layers). Using this platform, new applications can be created by enabling the devices to interact without relying on a central control node. The report also describes the basic design ideas of a computer connected interface to also relay information from the home automation system to the Internet.

  • 312.
    Håll, Peter
    KTH, Tidigare Institutioner, Teleinformatik.
    IPv61996Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 313.
    Höglund, Rikard
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Lightweight Message Authentication for the Internet of Things2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    During the last decade, the number of devices capable of connecting to the Internet has grown enormously. The Internet of Things describes a scenario where Internet connected devices are ubiquitous and even the smallest device has a connection to the Internet. Many of these devices will be running on constrained platforms with limited power and computing resources. Implementing protocols that are both secure and resource efficient is challenging. Current protocols have generally been designed for mains powered devices; hence, they are not optimized for running on constrained devices. The Constrained Application Protocol (CoAP) is a protocol for network communication specifically designed for constrained devices. This thesis project examines CoAP and presents an extension that adds authentication in a way that is suitable for constrained devices, with respect to minimizing resource use. The proposed solution has been compared and contrasted with other alternatives for authentication, particularly those alternatives used with CoAP. It has also been implemented in code and experimentally evaluated with regards to performance versus vanilla CoAP.

    The main goal of this project is to implement a lightweight authentication extension for CoAP to be deployed and evaluated on constrained devices. This extension, called Short Message Authentication ChecK (SMACK), can be used on devices that require a method for secure authentication of messages while using only limited power. The main goal of the extension is to protect against battery exhaustion and denial of sleep attacks. Other benefits are that the extension adds no additional overhead when compared with the packet structure described in the latest CoAP specification. Minimizing overhead is important since some constrained networks may only support low bandwidth communication.

  • 314.
    Högström, Andreas
    et al.
    KTH, Tidigare Institutioner, Teleinformatik.
    Åsbrink, Anders
    KTH, Tidigare Institutioner, Teleinformatik.
    S.U.N.E. - Secure User Network Environment1998Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In today's society, an increasing number of people geographically apart need to communicate to each other in a secure manner. We have discovered that very few existing systems provide this. Therefore, we have developed an easy-to-use Internet chat system with secure communications. This system is described in this report. The entire system is written in Java, which makes it platform independent. The report describes how the security is obtained and how the well the system scales when the number of users increases. It also describes how the usability of the system is affected by the security and the measurements done to evaluate this. The report further more describes the measurements taken to make the system easy to use and portable.

  • 315.
    Hörlin, Martin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Voice Over IP for Textphones: An implementation of an Analog Telephone Adapter enabling Baudot textphones to use real-time text over Real-time Transport Protocol using open-source code and hardware solutions2008Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In this thesis we will discuss how to implement a ToIP device that enables communication with a standard textphone over Internet Protocol using open software and hardware solutions. We will make an analog to telephone adapter capable of supporting Baudot textphones with the help of the software Asterisk, Open Baudot and the hardware platform IP04. We will discuss if the use of this device, if it is outdated already. We have performed practical testing of our solution and compared it with a voice channel setup.

  • 316.
    Hübinette, Daniel
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Occupancy Sensor System: For Context-aware Computing2007Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This masters thesis project, "Occupancy Sensor System", was conducted at Kungliga Tekniska Högskolan (KTH), Stockholm, Sweden, during the period 2007-04-24 – 2007-12-17. The goal of the project was to design an occupancy sensor system that determines if there exists more than one person in a defined region. The output of this system is for use in a context-aware system at the KTH Center for Wireless Systems (Wireless@KTH).

    The system is important because there is a need for specific input to context-aware systems concerning occupancy of spaces and because this thesis has focused on a problem that enables new complex and interesting services. Additionally, the specific problem of determining not only occupancy, but if this occupancy is zero, one, many has not been widely examined previously. The significance of zero occupants indicating an empty room has already been recognized as having economic and environmental value in terms of heating, ventilating, air-conditioning, and lighting. However, there has not been an effort to differentiate between a person being alone or if more than one person is present. A context-aware system might be able to use this later information to infer that a meeting is taking place in a meeting room, a class taking place in a classroom or that an individual is alone in a conference room, class room, etc. Thus enabling context-aware services to change their behavior based upon the differences in these situations.

    An occupancy sensor system prototype was designed to monitor a boundary by using a thermal detector, gumstix computer, an analog to digital converter prototype board, laptop computer, and a context broker. The testing and evaluation of the system, proved it to be sound. However, there are still further improvements and tests to be made. These improvements include: dynamic configuration of the system, communication between the different system entities, detection algorithms, and code improvements. Tests measuring accuracy of a detection algorithm and determining optimal detector placement need to be performed. The next step is to design applications that use the context information provided from the occupancy sensor system and expand the system to use multiple detectors.

  • 317.
    Ibrahim, Muhammad
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Ethernet in Steer-by-wire Applications2011Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    A Controller Area Network (CAN) is a multi-master serial data communication bus designed primarily for the automotive industry. It is reliable and cost-effective and features error detection and fault confinement capabilities. CAN has been widely used in other applications, such as onboard trains, ships, construction vehicles, and aircraft. CAN has even been applied within the industrial automation segment in a range of devices such as programmable controllers, industrial robots, digital and analog I/O modules, sensors, etc. Despite its robustness and other positive features, the CAN bus has limitations in form of limited maximum data rate and maximum bus length. Also the CAN network topology is rigidly fixed which is a severe limiting factor in some of its application cases, therefore several industrial actors are evaluating alternatives to CAN.

    Ethernet is one of the potential candidates to replace CAN. It is a widespread and well knowntechnology, easily accessible, and many off-the-shelf solutions are available. It can support extended networks and offers wide possibilities in terms of network topology thanks to active switches. It features very high bandwidth, which has increased systematically from 10 Mbps to 100 Gbps year after year, always preserving backward compatibility to the maximum possible extent.

    The purpose of this thesis project is to investigate the possibility of replacing the CAN bus with Ethernet according to the following requirements:

    • Standard off-the-shelf components and software stacks
    • No modification of the network node application software, i.e. messages formatted accordingto CAN protocols must be transferred by means of Ethernet.

    A main issue is that CAN is time deterministic; it is always possible to predict the maximum latency in a message transfer. On the other hand Ethernet is still considered unreliable for time-critical applications, although the advent of Ethernet switches has minimized this non-deterministic behavior.

    A unique approach to this issue is offered as a result of the work done by Time Critical Networks, a newly started Swedish company. Their tool makes it possible to calculate the maximum forwarding time of a frame in an Ethernet network. This tool may make it possible to validate the use of Ethernet for time-critical applications.

    CPAC Systems, a company in the Volvo group which develops and manufactures steer-by-wire systems based on the CAN technology, wishes to verify whether Ethernet could now be considered as a solution to complement or replace CAN, thus overcoming CAN’s limitations. This verification is the goal of this master thesis project.

    The work was carried out through three different phase:

    • First we performed a theoretical evaluation by modeling the Ethernet network using Time Critical Network’s tools.
    • Next we verified the results by implementing the modeled CAN/Ethernet network that was previously modeled.
    • Finally, we validated the solution by directly testing the modeled CAN/Ethernet in combination with CPAC System’s steer-by-wire technology.

    The results obtained show that Ethernet in combination with Time Critical Network’s modeling tool, when it comes to time-determinism, can be a complement and/or an alternative to the CAN bus.

  • 318.
    Ibrahim, Thabit
    KTH, Tidigare Institutioner, Teleinformatik.
    Image Watermarking for Secure Image Communication1999Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In this paper we use watermarking to embed a certain message into a digital image, We present, test, and compare four message coding algorithms. These algorithms are based on repetition coding, BCH coding, a combination of these two, and erasure-correcting coding. We consider three criteria, robustness,  number of changed pixels, and complexity, in comparing our algorithms. We will show that the way of encoding the embedded message can affect the robustness of the watermark while using the same watermarking technique.

  • 319.
    Immonen, Mia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    SIGTRAN: Signaling over IP -- a step closer to an all-IP network2005Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The mass popularization of telecommunication services in recent years have resulted in a heavily loaded signaling network. The Signaling System number 7 (SS7) is used in fixed and wireless networks and is needed for call control and services such as caller ID, roaming, and for sending SMS. The traditional SS7 networks are expensive to lease and to expand, hence a new suite of protocols have been designed to carry signaling messages over IP. This suite contains a transport protocol called Stream Control Transmission Protocol (SCTP) and various user adaptation layer protocols such as M2PA, M2UA, M3UA, and SUA. To transport the highly loss and delay sensitive signaling messages over IP, it is mandatory that the transport protocol meets the high performance requirements of SS7. Not before the IP-solution has been tested in detail, will it replace significant parts of the national telephone network.

    In this thesis, the failover duration in the case of link failure was tested using the feature of SCTP called multi-homing. The results suggest that carrying SS7 signaling traffic over IP is possible, since the failover duration does not exceed the required limit.

  • 320.
    Irstad, Noel
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Data- och elektroteknik.
    Fredrik, Stjerne
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Data- och elektroteknik.
    Governing of access point for stations in an 802.11 network with a repeater to achieve higher throughput: Designing and implementing an algorithm on Inteno's OpenWRT based access points2016Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    When using a wireless repeater in a network, an overlap zone between the repeater and the primary access point that holds the internet connection is created. The theoretical throughput for connections through the repeater is reduced by half since the repeater can’t send and receive data at the same time when using only one channel which was the case in this thesis.

    To solve the problem with the overlap zone, an algorithm that runs in the form of a bash script on two openWRT-based access points where one acts as a repeater and the other one is a gateway with an internet connection was developed. The script uses the signal strength value (RSSI) to decide whether a wireless device is located within the overlap zone by comparing the measured value against a set threshold where the gateway still delivers higher throughput than the repeater. Wireless devices in the overlap zone are blocked on the repeater and will then connect to the gateway instead. Wireless devices that are located outside the overlap zone will connect to the access point that yields the strongest signal strength. The throughput to the gateway was measured at several locations with different signal strengths to both the gateway and the repeater.

    Wireless devices within the overlap zone that were connected to the repeater before the script was run gained a higher throughput after the script was run and made it connect directly to the gateway instead.

  • 321.
    Isaksson, Marcus
    KTH, Skolan för teknik och hälsa (STH), Data- och elektroteknik.
    Utvärdering av Windows RT för portning av Mario Framework2013Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Ericsson har utvecklat ett ramverk för multimediakommunikation som heter Mario. Mario kan användas för att sätta upp video- och ljud-samtal över IP och finns fungerande på Android och iOS. Mario är en del av web browsern Bowser som finns att hämta på Google Play eller App Store. Bowser möjliggör att köra WebRTC applikationer skrivna i HTML5 och JavaScript på Android och iOS.

    Nu när Microsoft släpper sina nya plattformar, Windows RT, Windows 8 och Windows Phone 8 så finns ett intresse att försöka flytta detta ramverk till dessa plattformar. Vi kommer göra ett försök att porta Mario till Windows RT. Anledningen till att Windows RT valdes är för att det är den första plattformen att släppas av de tre nämnda produkterna.

    Plattforms APIet som används i Windows RT kallar för Windows Runtime (WinRT). Många delar av det här APIet delas med Windows Phone 8 och hela WinRT APIet exponeras i Windows 8. Det här betyder att förutsatt att koden designas på rätt sätt så borde den gå att flytta mellan Windows RT, Windows 8 och Windows Phone 8 utan problem. Windows RT är ett operativsystem utvecklat för att fungera på datorer som använder ARM-baserade processorer.

    För att Mario ska kunna fungera på WinRT så måste följande mål uppfyllas:

    • De open-source bibliotek som används av Mario måste byggas på Mario.
    • C/C++ kod måste kunna köras på Windows RT plattformen.
    • Mario ramverket måste integreras med video- och ljudfångning i operativsystemet.

    Vad det gäller open-source projekt så ligger det under en sådan licens (LGPL) som gör att källkoden inte får ändras utan att hela källkoden till de projekten som använder open-source koden också släpps som open-source. Ericsson vill inte att Mario ska släppas som open-source utan vill själva ha kontroll på källkoden. Av denna anledning kommer vi utreda om det är möjligt att bygga dessa bibliotek utan att ändra i koden.

    I och med att Mario är skrivet i C och C++ så måste det också utredas hur vida det är möjligt att köra C/C++ kod i Windows RT. Vad det gäller video- och ljudfångning måste Windows RT APIet utredas för att se hur man använder det för just detta.

  • 322.
    Islam, Md. Safiqul
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    A HTTP Streaming Video Server with Dynamic Advertisement Splicing2010Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The Internet today is experiencing a large growth in the amount of traffic due to the number of users consuming streaming media. For both the operator and content providers, streaming of media generates most of its revenue through advertisements inserted in the content. One common approach is to pre-stitched (i.e. insert) advertisements into the content. Another approach is dynamic advertisement insertion, which inserts advertisements at run-time while the media is being streamed. Dynamic advertisement insertion gives operators the flexibility to insert advertisements based on context, such as the user's geographic location or the user's preferences. Developing a technique to successfully insert advertisements dynamically into the streaming media has several challenges, such as maintaining synchronization of the media, choosing the appropriate transport format for media delivery, and finding a splicing boundary that starts with a key frame. The details of these challenges are detailed in this thesis.

    We carried out extensive research to find the best transport format for delivery of media and we studied prior work in an effort to find an appropriate streaming solution to perform dynamic advertisement insertion. Based upon this research and our study of prior work we identify the best transport format for delivery of media chunks, then propose, implement, and evaluate a technique for advertisement insertion.

  • 323.
    Ismail, Ziad
    KTH, Tidigare Institutioner, Teleinformatik. KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Enhancing Usability in a Distributed System1998Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This report examines the digital information cycle (searching, viewing, and creating), and argues that the problems that are encountered should not be solved one at a time. Instead we must look at the system as a whole and redesign it.

    The report concludes that there are five areas that can enhance the usability in an information system: organize information in classes, distributed and automatic identification, separate functions from content, deal with uncertainty, and provide automatic environment management.

  • 324.
    Jacob, Kane
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik.
    Gudey, Bala Bhaskar
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik.
    Co-Design of Antenna and LNA for 1.7 - 2.7 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In a radio frequency (RF) system, the front-end of a radio receiver consists of an active antenna arrangement with a conducting mode antenna along with an active circuit. This arrangement helps avoid losses and SNR degradation due to the use of a coaxial cable. The active circuit is essentially an impedance matching network and a low noise amplification (LNA) stage. The input impedance of the antenna is always different from the source impedance required to be presented at the LNA input for maximum power gain and this gives rise to undesired reflections at the antenna-LNA junction. This necessitates a matching network that provides the impedance matching between the antenna and the LNA at a central frequency (CF). From the Friis formula it is seen that the total noise figure (NF) of the system is dependent on the noise figure and gain of the first stage. So, by having an LNA that provides a high gain (typically >15 dB) which inserts minimum possible noise (desirably < 1 dB), the overall noise figure of the system can be maintained low. The LNA amplifies the signal to a suitable power level that will enable the subsequent demodulation and decoding stages to efficiently recover the original signal. The antenna and the LNA can be matched with each other in two possible ways. The first approach is the traditional method followed in RF engineering where in both the antenna and LNA are matched to 50 W terminations and connected to each other. In this classical method, the antenna and LNA are matched to 50 W at the CF and does not take into account the matching at other frequencies in the operation range. The second approach employs a co-design method to match the antenna and LNA without a matching network or with minimum possible components for matching. This is accomplished by varying one or more parameters of either the antenna or LNA to control the impedances and ultimately achieve a matching over a substantial range of frequencies instead at the CF alone. The co-design method is shown to provide higher gain and a lower NF with reduced number of components, cost and size as compared to the classical method.

    The thesis work presented here is a study, design and manufacturing of an antenna-LNA module for a wide frequency range of 1.7 GHz – 2.7 GHz to explore the gain and NF improvements in the co-design approach. Planar micro strip patch antennas and GaAs E-pHEMT transistor based LNA’s are designed and the matching and co-design are simulated to test the gain and NF improvements. Furthermore, fully functional prototypes are developed with Roger R04360 substrate and the results from simulations and actual measurements are compared and discussed. 

  • 325.
    Jakobsson, Per-Johan Simon
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Cloud-Based Alerting System for IP-Telephony: A prototype development2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    An increasing number of people in Sweden are having problems with their hearing ability. The three major tools to aid hearing-impaired and deaf individuals are: hearing aids, special telephony, and alerting systems. Both hearing aids and telephony have seen a huge technical development. Hearing aids have gone from huge ponderous devices to small delicate in-ear devices. Simple text telephones have evolved into total conversation telephones with audio, video, and text all operating in real time. Although smart lamps and other alerting services not specifically made for hearing-impaired individuals do exist, the development of alerting system is unsatisfactory. The gap in technology is a huge problem and integration between modern products and alerting systems is getting harder. This thesis explores how to close this gap. The result of this thesis project is a prototype that provides the missing technological link between an alerting systems and modern smart devices. An eventual product should support all kinds of services, but the prototype is limited to solving the problem of connecting an alerting system to a modern total conversation telephones. The prototype was evaluated and based on the evaluation data a timeline was created. An overall positive response towards the product exists and the timeline had adding more third party services (such as Skype and FaceTime) as a high priority. The complete timeline as well as adding Signal Initiation Protocol support is left as future work.

  • 326.
    Janson, Robert
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    Mottaghi, Amir
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    FPGA-design av en STDM-baserad multiplexer för seriell multiprotokollskommunikation2012Independent thesis Basic level (degree of Bachelor), 10,5 poäng / 16 hpOppgave
    Abstract [en]

    The remotely operated underwater vehicles that the client develops have needs of different kinds of data channels. In order to minimize the need of physical cable between the control unit and a ROV, a multiplex protocol has been developed. The protocol has been designed with the aim of using the bandwidth of the transferring link as efficient as possible.

    The different kinds of data channels used during this thesis project is; RS232, RS485 and CAN. ROM and FIFO-memories have been used to be able to effectively manage the different data channels. All the reading and sending of these channels have been implemented in FPGA-technology, the coding is made generic so that it will be easier to add more channels to the system in the future.

    The multiplex protocol is a modified version of the method STDM and it is a proprietary protocol. Calculations has been made in MatLab to ensure that the protocol does not exceed the maximal bandwidth that is available. The protocol utilizes the error-detecting technique CRC for the purpose of error detection.

    A PCB has been developed during this thesis project, the PCB is made so that the different data channels have connection with the FPGA circuit.

  • 327.
    Jansson, Christian
    KTH, Tidigare Institutioner, Teleinformatik.
    Making the communication network aware of the user's location1998Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis report discusses and summarises the concerns for making the communication network location aware. Along with the motivation a collection of services is presented, some more useful than the others.

    Several different techniques that could be used to acquire location awareness are presented. Each presentation includes both a technical description, a section with the pros and cons, and a summary of how well it corresponds to the desired characteristics.

    At the end of the report the implementation of a prototype call routing application is described, as an example of a location aware service. It enables automatic routing of phone calls based on the user=92s location and is built with help of the Smart Badge and International Multimedia Teleconferencing Consortium (IMCT) Call Management Agent system.

  • 328.
    Jansson, Fredrik
    et al.
    KTH, Tidigare Institutioner, Teleinformatik.
    Larsson, Marcus
    KTH, Tidigare Institutioner, Teleinformatik.
    Portal Payment Possibilities: for a start-up company2000Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The corporate climate for start-up companies in Sweden has been extremely good for the last couple of years. A lot of small companies have been entering the Internet business arena in different areas such as consulting, content providing, and system developing. Especially the mobile fraction of the Internet field is today a hot topic in Scandinavia and it is rapidly spreading to the rest of the world. This Master of Science thesis investigates how a small start-up company operating in the mobile Internet field could be able to let its customers pay for the companies services.

    Different payment possibilities have been described, compared and evaluated. Amongst the possible solutions are direct Internet payment, credit cards, and micro payment systems. The evaluated solutions are mainly focused on enabling Internet based payments to take place, but the goal is to be able to conduct payments using a standard mobile device. Several technologies could be used to extend the Internet solution to the mobile market. Techniques that can be used and are evaluated in this thesis are: CTI, SMS, WAP, and SAT.

    When offering payment possibilities on the Internet an obvious problem is the security matters. Nevertheless this thesis describes and evaluates the possible solutions available today and a large factor when extending the Internet based payment method to the mobile area are the user confidence and easy to use factors. Furthermore the chosen solution should be possible for a small company to implement. That means that no hardware implementations in the mobile device are acceptable.

    Two possible solutions have been implemented and are described in the report. First a real credit card solution for the web case. Second the web solution has been extended to work in a wireless GSM environment using SMS.

  • 329.
    Jansson, Michael
    et al.
    KTH, Tidigare Institutioner, Teleinformatik.
    Eriksson, Niklas
    KTH, Tidigare Institutioner, Teleinformatik.
    Management of voice based group communication2000Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Communication between groups of people is becoming increasingly desirable as mobile telephony is merging with the existing Internet. For GSM, this is being done via GPRS, which is the first step towards the standard for 3G mobile telephony systems, UMTS. Managing groups and the members within them in order to ensure consistency, is a challenging task. The use of multicast is a great help, especially when designing a solution for WANs, where flooding should be avoided.

    This report discusses some of the aspects of group communication and group management. The report compares alternative membership algorithms and describes a solution for adding group support to Ericsson Daemon system. Also, a prototype working like a voice newsgroup is described.

  • 330.
    Jansson, Rasmus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Completion of the software required for a high-temperature DLTS setup2013Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    The main purpose of this thesis was to examine the communication problems with the DLTS set up in the Division for Electricity at Ångström Laboratory in Uppsala, Sweden, and to make the DLTS software complete. The set up consisted of a C/V meter, a pulse generator, a temperature controller and a PC with a control program written in LabVIEW. It was found that the software had been constructed to fit another set of instruments than the set up currently used at Ångström Laboratory. The task was therefore to properly integrate the correct control commands of those instruments into the software.

  • 331.
    Janzon, Henrik
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Medina Maturana, Gonzalo
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Utvärdering och beslutsunderlag för placering av IT-plattform: En fallstudie av Microsoft SharePoint2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Tillgången på så kallade molntjänster är något som har ökat de senaste åren, vilket inneburit att många klassiska tjänster nu även erbjuds i molnet. Ett beslut ifall denna typ av lösningar skall användas, påverkas av många olika aspekter som ofta är unika för den specifika organisationen. Således finns ett behov av ett underlag som tillgodoser de kriterier som är viktiga för organisationen, men också ger en överblick av de olika alternativen. Samtidigt måste även hänsyn tas till organisationens subjektiva uppfattning vid beslutsfattandet, för att på så sätt kunna genomföra ett genomtänkt och välgrundat val om vilket alternativ som bör användas. Målet med undersökningen har varit att bidra med ny information inom området och påvisa hur det praktiskt kan gå till att ta fram denna typ av underlag för att motivera sitt beslut. Detta har undersökts genom att i en fallstudie jämföra tre olika plattformsalternativ för Microsoft SharePoint och rangordna dessa efter en redan befintlig metod för att ta beslut baserade på flera kriterier. Valet av metod föll på Analytic Hierarchy Process (AHP) vilket är en etablerad metod som även används inom många andra områden och lämpar sig för beslut baserad på subjektiva uppfattningar. Undersökningen har visat att det är möjligt att använda AHP för denna typ av jämförelse, för att få en överblick mellan de olika alternativen och för att slutgiltligen få fram det alternativ som är lämpligast, vilket i detta fall blev molnlösningen.

  • 332.
    Jaoua, Mohamed
    Linköpings universitet, Institutionen för systemteknik, Kommunikationssystem.
    Development of an FPGA-based High-Speed Wireless Communication System in the 60GHz Frequency Band For CERN facilities and 5G deployment2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 333.
    Jarrar, Asim
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    Context Server support for opportunistic andadaptive mobile communication2003Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This master’s thesis extends the functionality and intelligence of the Personal Digital Assistant (PDA) when roaming in a WLAN or a GPRS network. This is accomplished by introducing a Context Server database in the new mobile IP network. The Context Server collects knowledge called Context Data, concerning the network topology, network quality at various locations, sensor data from PDAs, and network services provided at various locations and by various hosts. This distributed knowledge will enhance and extend the functionality of the PDAs by providing and facilitating more network services to the user. With the help of this Context Data the PDA will extend it’s intelligence and make routing and data transmission decisions that are more adapted to the network topology and the service that is available to the user at a specific geographical location. The PDAs will roam and access multimedia services via different wireless access networks (e.g., GPRS, WLAN, UMTS, etc.). PDAs requesting services achieve more optimal quality and utilize the best available data transmission rate by using the Context Data. Example of services that can be provided are downloading of MP3 encoded songs from a database or other PDAs, communication with other GPRS and WLAN enabled devices, streaming Internet radio, weather reports on demand, watching video clips, and Internet access. These services can be received on a laptop, mobile host, or any device with an interface to a GPRS and a WLAN network.

    Today the telecom industry is having financial problems. Everyone wants to decrease costs and achieve more functionality and offer new services with little additional investment in the existing wireless networks. This thesis should contribute to future wireless network architecture by enabling access at the appropriate cost and quality by using the available network resources more intelligently. Based upon a prototype with all the network elements involved, we are able to analyze if this idea is technically possible to implement and scaleable for use by today’s society with it’s increasing demands and desire for high quality services while they are mobile.

  • 334.
    Jaurén, Daniel
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Generic Data Structure for a Security Policy Database2008Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    IPsec makes secure Internet infrastructures more feasible, as its security services offer protection for IP traffic at the network layer. It is a very dynamic protocol suite, consisting of several protocols that enable a number of different security services. As IPsec enables flexible security, there is a need for agreements between the parties. All network nodes that utilize IPsec need to keep track of their agreements with their peer nodes, this information is stored in a Security Policy Database (SPD).

    In a network environment where thousands of pairs of nodes may communicate, it is important that lookups in the SPD occur quickly. The SPD usually operates with a small number of agreements, which suggest that the data structure it utilizes should be rather simple. However, the data structure should scale properly, even when the number of agreements increases to a very large number. This masters thesis examines existing implementations of a SPD and the existing data structures used for SPD implementation. It then tries to identify what makes a good implementation. Subsequently, a generic data structure is proposed for use as a SPD.

  • 335.
    Jernberg, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Metoder för att sända meddelanden från QT Systems fastighetssystem till smarta telefoner2016Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Företag har länge kunnat nå ut med information till kunder via traditionella metoder så som sms och e-post. I och med den stora populariteten hos smarta telefoner och sociala medier har information nu blivit extra viktigt. Med detta har det även kommit nyare sätt för företag att kommunicera med sina kunder så som via push-notifikationer till smarta telefoner och webbläsare eller via sociala medier.

    Projektet beställdes av QT Systems och hade som syfte att ge företaget en bättre inblick i vad de har för möjligheter när det gäller att nå ut med information till deras kunder. Målet med projektet var att finna den metod som bör passa bäst för att just QT Systems fastighetssystem ska kunna notifiera deras användare om olika händelser och att kunna visa att denna går att implementera i detta system.

    Under arbetets gång bestämdes det att push-notifikationer till en native app skulle vara den bästa lösningen. Det har även gjorts ett ”proof-of-concept” som visar att den valda metoden kommer gå att implementera i QT Systems fastighetssystem och åtminstone nå ut till smarta telefoner som har Android eller iOS som operativsystem.

  • 336.
    Ji, Lin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Increasing Accuracy of Location Determination: Exploiting Phase Change Reconstruction and Timing Measurements2007Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The thesis deals with improving location determination when using time of flight of radio signals to determine the location of a radiator. The goal of this project is to enhance an existing wireless data access point to perform an accurate measurement of the time of arrival of a data signal from a transmitter, and to combine this information with information from additional wireless data access points to determine the location of the transmitter.

    There have been a number of earlier efforts in indoor location determination system using different technologies. Many of which used signal strength analysis and they have low tolerance to moving obstacles such as humans, which frequently are the most usual dynamic obstacles in indoors. In this thesis, the proposed solution utilizes time stamping and sample correlation to utilize properties of the signal waveform, which has not previously been examined by researchers other than the examiner and advisor.

    The main contribution of the project is a detailed analysis and design of a solution, as well as a comparison with other potential solutions. The main purpose of this solution is to increase the timing accuracy to below the duration of a single symbol. The wireless device that has been analyzed implements the IEEE 802.11b protocol. Several investigations have been done to determine the best way of extracting information from the 802.11b data frame and symbol sequence; here we utilize a correlator to determine the time of arrival of a specific sequence of symbols in a data frame. The time stamping of a stream of samples has been implemented in an Altera FPGA to get a deterministic computation time.

    Instead of decoding the incoming I&Q signals and mapping them to bits, the correlator is used to detect the unique sequence containing PSK encoded and Barker code spread scrambled ones , as this sequence always appears at the start of each data frame. The advantage of this approach is that using of samples of the waveform instead of bits gives a significant enhancement in timing resolution.

    The design documents of this work include detailed descriptions, simulations, and plots. A number of simulations have been done to show the timing accuracy and standard deviation, as well as comparisons with several different approaches. Several potential optimizations have also been discussed in the report.

    Simulation code for MATLAB and implementation code for the FPGA has been included in appendices in the end of this thesis.

  • 337.
    Jiang, Zuoying
    KTH, Skolan för elektro- och systemteknik (EES), Kommunikationsnät.
    Predicting Service Metrics from Device Statistics in a Container-Based Environment2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Service assurance is critical for high-demand services running on telecom clouds. While service performance metrics may not always be available in real time to telecom operators or service providers, service performance prediction becomes an important building block for such a system. However, it is generally hard to achieve. 

    In this master thesis, we propose a machine-learning based method that enables performance prediction for services running in virtualized environments with Docker containers. This method is service agnostic and the prediction models built by this method use only device statistics collected from the server machine and from the containers hosted on it to predict the values of the service-level metrics experienced on the client side. 

    The evaluation results from the testbed, which runs a Video-on-Demand service using containerized servers, show that such a method can accurately predict different service-level metrics under various scenarios and, by applying suitable preprocessing techniques, the performance of the prediction models can be further improved. 

    In this thesis, we also show the design of a proof-of-concept of a Real-Time Analytics Engine that uses online learning methods to predict the service-level metrics in real time in a container-based environment.

  • 338.
    Jin, Shanlun
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Implementation and Analyses of the Mobile-IP Protocol: Under Windows2008Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This report is the result of a masters degree project conducted at the Department of Teleinformatics at the Royal Institute of Technology starting from the autumn 1996. The area investigated is the Mobile Internet Protocol, especially its implementation under Windows NT environment. Network driver writing under Windows NT was practised. Recent development in improving Mobile IP protocol to support micro-mobility have also been investigated.

  • 339.
    Jin, Youbei
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Integration and assessment of streaming video content and API development into a spaced repetition service2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    There are a lot of spaced repetition system based online learning services available nowadays, but none of them are popular or widely accepted as a good means for studying. The problem of these services is, instead of exploiting and utilizing the possibility of modern technology, they simply brought this old school learning method to the web as an application with exactly the same experience as one could have with textbooks and flash cards. This master’s thesis project concerns Sharplet, a spaced repetition system based web service, who is trying to stand out by offering some features that none of the other comparable services have. One of these features is the integration of YouTube video clips, so that in addition to text and pictures, study materials may now include both audio and video material.

    This thesis begins by reviews spaced repetition systems in general, and then focuses on some of the existing services and how to provide a better service. Next the thesis describes the design, implementation, and evaluation of a new service that includes both audio and video content. The main practical result of this master’s thesis project is a working prototype audio and video enabled spaced repetition based service. Unfortunately, the actual performance of this prototype is unacceptable, hence there is a need to improve its performance before it can be integrated with the production spaced repetition system.

  • 340.
    Joelsson, Tomas
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Mobile Web Browser Extensions: Utilizing local device functionality in mobile web applications2008Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Mobile web browsers of today have many of the same capabilities as their desktop counterparts. However, among the capabilities they lack is a way for web applications to interact with local devices. While today’s mobile phones commonly include GPS receivers and digital cameras, these local devices are currently not accessible from within the browser. The only means of utilizing these devices is by using standalone applications, but such applications lack the versatility of web browsers. If a mobile browser could utilize these local devices, then a mobile application could run within the browser, thus avoiding the need for specialized client software.

    This thesis suggests an approach for adding such capabilities to mobile browsers. In the proposed method, scripted access to local device functionality is facilitated by a local Java application. This application acts as a proxy server and allows the browser to call methods exposed by the local Java APIs. Both the benefits and some security concerns of this approach are examined. The benefits are further highlighted through two example web applications which utilize local devices.

  • 341.
    Johansson, Carl
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Kavosi, Soren
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Automating Interactions with Web Services: NFC based attendance software in Java2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Today we use an obsolete way of handling information regarding which student and/or teacher is attending which class/lab/seminar, attendance is written down on a piece of paper and collected so that an administrator can manually enter this information to some data processing system.

    This method is far from optimal and demands a lot of time and resources from administrators, teachers, and students. Correct gathering of attendance is important since it is required for specific parts of some courses. We propose to automate the collection of this attendance data, thus enabling students and teachers to simply swipe their NFC-enabled KTH access card in order to enter their name on an attendance list. This will be achieved by creating an application that adds a student to an attendance list by reading information using a NFC/RFID reader and mapping the card’s UID to a KTHID (a locally unique identifier used within the university) using a database. The resulting attendance list should be formatted in such a fashion that it can easily be uploaded to systems such as KTH Social and Daisy. Ideally these systems will be extended so that instructors/teachers can use this attendance list to automatically create the appropriate entries in these systems to record the student’s participation in the indicated activity – in the process avoiding a lot of manual labor and improving the accuracy of the process.

    An additional problem is that there is currently no unified system that connects the KTH access card database (BRAVIDA) to the KTH LDAP database (which stores information about KTH students, faculty, and staff). This means that each student’s access card UID must manually be added to a database together with the student’s KTHID. However, once this database entry has been made, we can then map from a card number to a KTHID (or the reverse).

    The purpose behind and expected result of this thesis is a functional prototype of an application that creates an attendance list by reading data from the student or teacher’s access cards using a NFC reader. This will hopefully stimulate further digitalization in KTH and also encourage more courses to utilize such access card based attendance lists. The result should be less manual effort by students, faculty, and staff, as well as more accurate and timely filing of attendance information for courses.

  • 342.
    Johansson Enell, Lina
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Datateknik och informatik.
    Hoffman, Emelie
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Datateknik och informatik.
    Den ständiga kampen mellan serif och sans serif: Typografins digitala utveckling2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta examensarbete är en del av utbildningen Kandidatpåbyggnad med inriktning Informatik som är ett påbyggnadsår för Grafisk design och webbutveckling på Jönköping University: School of Engineering.

    Vid en snabb granskning av hemsidor idag går det enkelt att se att det är dominerande att använda sans serif-typsnitt både till rubriker och i brödtext. I grafiska utbildningar lärs det ut att för bäst läsbarhet bör serifer användas i brödtext. Syftet med examensarbetet var att undersöka vad som påverkar läsbarheten på en digital skärm och varför det inte är vanligare att använda serifer på en webben, med tanke på hur långt tekniken kommit idag med nya högupplösta skärmar som inte borde påverka användningen av serifer. Syftet var även att undersöka om val av typografi idag alltid baseras på typografiska regler.

    Resultatet visade att ett serif-typsnitt upplevs som mer lättläst än ett sans serif-typsnitt oberoende på om de läses på en digital skärm eller på ett tryckt papper. Resultatet visade även att dominationen av sans serif-typsnitt på webben beror på en vana som hänger kvar sen förr, men att detta troligen kommer att förändras i framtiden.

    Det finns geografiska begränsningar i arbetet, då examensarbetet endast undersöker södra Sverige. För att öka validiteten kunde representanter från hela Sverige ha deltagit. Det hade kunnat påverka och förändra resultatet. Undersökningen hade kunnat förbättras generellt genom att utveckla den och använda fler typsnitt, för att få ett tydligare svar på frågeställningen den undersökte. Även detta hade kunnat påverka resultatet till något annat.

  • 343.
    Johansson, Filip
    et al.
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system.
    Lindström, Christoffer
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system.
    Inter-Process Communication in a Virtualized Environment2018Independent thesis Basic level (degree of Bachelor), 10,5 poäng / 16 hpOppgave
    Abstract [en]

    Selecting the correct inter-process communication method isan important aspect of ensuring effective inter-vm and inter-container process communication. We will conduct a study ofIPC methods which might be useful and fits the Qemu/KVMvirtual machine and Docker container environments, and se-lect those that fit our criteria. After implementing our chosenmethods we will benchmark them in a test suite to find theones with highest performance in terms of speed. Our resultsshow that, at the most common message sizes, Unix DomainSockets work best for containers and Transparent Inter Pro-cess Communication has the best performance between vir-tual machines out of the chosen methods.

  • 344.
    Johansson Holmbäck, Fredrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Sundström, Max
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Undersökning av vissa beläggningars påverkan på antenners effektivitet i tågmiljö2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.

    As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules. Finally a sample coating taken directly from a car was tested to determine how closely the other coatings resembled what appeared in normal use.

    Most of the coatings gave similar results; little or no loss of efficiency and a lowering of the resonance frequency by some 75 MHz, with both iron powder samples, the ore granules and the sample coating proved nearly identical in results. Thick layers of snow gave a noticeable drop in efficiency, as did the presence of any amount of water, which also greatly affected the resonance frequency.

  • 345.
    Johansson, Lars
    KTH, Tidigare Institutioner, Teleinformatik.
    SNMP based management for Voice Response Systems1998Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The need for management, supervision, and control of different devices connected to networks has increased. The reasons are the increased complexity of the attached devices and a desire to supervise all devices from one centralized place.

    In this project, a Voice Response System (VRS) was to be manageable by using the Simple Network Management Protocol (SNMP).

    This report is divided into three sections. The first section describes the VRS, its functionality, and how it can be used. The second section explains how the SNMP protocol and the related protocol AgentX works, and in which versions it exists. The VRS is running under Windows NT, so how SNMP works in the Windows operating system family is also described. The last section deals with the development of a manageable VRS including, which information should be manageable, which protocol and API should be used to achieve a good solution. In this last section, a prototype implementation of the management system for the VRS is described. The prototype does not cover the whole proposed solution but the implemented parts works and it can be extended easily.

  • 346.
    Johansson, Sonny
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Data- och elektroteknik.
    “Bring your own device” i svenska företag och organisationer2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Most companies and organizations today depend on technology connected to the Internet. Schools and offices have therefore been providing computers, phones and other technology to the employees. The recent technological development and decline in prices for technology have contributed to making these products a part of everyday life for most people. This has made it very common for employees and students to bring their own devices into school and workplaces.

    The aim of this study is to define what "Bring your own device" means for Swedish companies and organizations and how it has been implemented in those. The aim is not mainly to generalize to all Swedish companies but create an understanding how the trend is used to provide a basis for continued research in this area. The questions this thesis aims to answer is:

    1. What does the term "Bring your own device" mean in the Swedish organizations and companies in which it is implemented?
    2. How is "Bring your own device" implemented in Swedish organizations and companies?
    3. What are the policies and guidelines for the Swedish organizations and companies that have implemented "Bring your own device", and how is compliance?

    A pragmatic approach has been used to incorporate previous studies while keeping the interview questions open to new approaches. The structure has been small-N studies that go deep into a number of cases, in order to more profoundly explain a phenomenon. Mail interviews have been used to collect data from the persons responsible for "Bring your own device" in the different organisations.

    The result shows that companies see "Bring your own device" as a trend where employees bring their own devices rather than firms providing employees with devices that they use privately. Respondents have not measured or examined how the introduction of BYOD has affected productivity. It seems, like in foreign studies, to be a lack of clear policies and guidelines regarding the phenomenon.

  • 347.
    Johansson, Staffan
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Port of OPC UA to gateway for industrial networks2013Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    HMS Industrial networks is a company that offers communication solutions for automation systems. There exists an abundance of different industrial network technologies and HMS manufactures gateways that translate and allow communication between the different networks.The multiplicity of network technologies introduces problems when it comes to monitoring the processes in an automation system. It is desirable to be able to access the process data through a single network technology and this is what OPC UA is used for. Briefly, OPC UA can be described as an interface for exchange ofprocess data in automation systems. HMS has noticed a rising trend in the interest for OPC UA and therefore wants to investigate the possibility to use OPC UA on their platform, the Anybus X-Gateway. The goal of this thesis has been to port an OPC UA stack, provided by the OPCfoundation, to the HMS operating system running on an Anybus X-Gateway. The port has been successful and has been verified by unit tests and a test application. Thus, a first step towards a complete OPC UA product has been taken. Further, the thesis presents a theoretical summary about real-time operating systems to explain their function and usage.

  • 348.
    Johansson Sävenberg, David
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Fiberoptisk nätplanering2015Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Denna studierapport handlar om hur man kan gå tillväga för att bygga upp ett fiberoptiskt bredbandsnät i stadsdelen Ersliden utanför Umeå. Arbetet har styrts efter en kravspecifikationför vad nätet ska klara av.

    Rapporten innehåller två delsystem. Det ena tar upp det fasta nätets uppbyggnad och det andra tar upp vilken trådlös accesspunkt nätet ska ha.

    I studien tas det upp vilken typ av fiber nätet ska använda sig av, hur noder och kanalisationska planeras och vilken typ av hårdvara som passar nätets kravspecifikation.

  • 349.
    Johansson, Victor
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Enhancing user satisfaction in 5G networks using Network Coding2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Network data rates are growing rapidly. The data rates provided to the customers by their network providers vary from Mbps to Gbps. However, rarely do users get the promised peak throughput.

    In cellular networks, network conditions change based on obstacles, weather conditions between the client and the base stations, and even the movement of objects and people. As a result of the changes in the radio link, the data transfer rate can change rapidly, hence devices needs to adjust their communications based on the currently available data rate.

    The Transmission Control Protocol (TCP) is widely used for reliable data transfer over networks. However, TCP was initially designed when link data rates were much lower than the link data rates commonly available today. As a result, TCP does not perform well at high data rates, despite some of the changes that have been made to the protocol to support high data rate links. Moreover, TCP has problems adapting to large changes in link bandwidth (not caused by congestion), resulting in a lower average throughput than the link could potentially deliver.

    This thesis evaluates two different versions of the TCP protocol (e.g., TCP Reno and Cubic TCP) and proposes a network coding scheme to enhance users’ experience when communicating over unstable radio links. The performance of the two TCP protocols and Random Linear Network Coding (RLNC) scheme were measured in an emulated network environment. The results of these measurements were analyzed and evaluated. The analysis shows that RLNC can provide a higher throughput than TCP over a network with high packet loss. However, RLNC is a UDP based solution and does not implement congestion control algorithms or reliability. A new solution is proposed that increases reliability and implements network adaptation in RLNC solutions.

    The results obtained in this thesis can be used to develop a new protocol to increases the quality of users’ experience in high loss networks.

  • 350.
    Johari Varnoosfaderani, Mohammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Economical Debug Station For debugging 3G modem2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Communication world is growing with an incredible high speed. Every day comes new technologies and give us more access and opportunities in work and life.

    One of the most important branches is small cells and similar product families.

    It extends from a simple telegraph codes to 3G W-CDMA and 4G LTE networks.

    It offers mobile network operators a cost-effective alternative to macro-only deployments for meeting growing coverage and capacity demands.

    Making products and bring it to market is one part of the job. It is important that product be fault free and reliable. Due to this comes our need for test and debugging.

    Test and debugging have high value in massive production.

    This research is subjected to a small cell modem, this modem has different parts like:

    - Download link and upload link through fiber optic cables for CPRI.

    - Network part which include Wi-Fi and LAN.

    - GPS module.

    - eUSB for customization of modem firmware.

    - Com, I2C and JTAG ports for debugging or reprograming the modem.

    We need to develop a debug station to make debugging easier on this modem and having clear compare results. It is important to have a CPRI tester and GPS signal simulator in our debug station.

    Beside all of these we need to make free standalone debug station which save us money and time, and from other side it should be as accurate as possible which make it reliable.

    One of important tests which should get done on test object is Boundary scan in debug station.

    Debuggers mentioned that it is hard to stop the test process in each level and from other side it is hard to find the faults with pass/fail results.

    In this project we try to implement all necessary tests in one and same debug station.

    Debuggers use separate stations for function test and boundary scan test and eUSB programing, with help of this debug station we have all of these 3 main tests in same station and debugger can work independently to repair the boards without interfering in production process or waiting to get time to use function test station or boundary scan tester .

    One of the Results is saving time from debugger’s side and this is more effective for company to save money and give faster and better repair service.

    We should use calibrated and the most accurate tools for testing to get best result. 

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