This master’s thesis is focused on IP mobility support for mobile users and their devices in IPv6-based wireless networks. Then the Mobile IPv6 (MIPv6) protocol was proposed for this purpose and that is also the main objective of the thesis. This consists of several basic sections and is organized as follows: The first one deals with the overview of the function of Mobile IP, which enables the mobility of nodes around the Internet, without a change of their original IP address. Moreover there are introduced the primary differences between MIPv6 and its previous version – i.e., MIPv4, proposed for IPv4-based environment. The second chapter of the master’s thesis thereafter describes detailed information about all the most important mechanisms and features of Mobile IPv6 and this way tries to explain principles of its functioning. Further the thesis analyses some of proposed MIPv6 extensions – i.e., Hierarchical Mobile IPv6 (HMIPv6), Mobile IPv6 Fast Handover (FMIPv6) a Fast Handover for HMIPv6 (F-HMIPv6) protocols, and mainly aim at signaling process during the handover of a mobile node. In the last main section of the master’s thesis an analytical method to evaluate the performance of IPv6-based mobility management protocols was proposed. Subsequently, this method is applied on the protocols which were mentioned above and are studied the effects of various network parameters on the performance of these protocols.

This Master´s thesis deals especially with exploration of the handover process and with searching for ways of in?uencing this process. The goal of this thesis is to create tools for recording of access point utilization and in?uence the handover of wireless clients based on the obtained data. An access point with open ?rmware, which allows low-level management, was necessary for practical tests. First chapter deals with a survey of current o?er of open ?rmware available for access points and then the appropriate candidate for this thesis is chosen – the OpenWRT project. Second chapter deals with the con?guration of OpenWRT system and basic settings of the chosen wireless router – TP-Link TL-WR1043ND. Next chapter deals with analysis of the handover process in wireless networks. Information obtained by this analysis is used during the creation of the graphic application. The fourth chapter presents the basics of Microsoft Native Wi-Fi API and introduces basic functions used by this API. Those functions were used during the creations of the application. Last two chapters present the created graphic application. The ?fth chapter deals with the application design and examination of its functionality and used functions. Last chapter then documents usability of the application in real environment.

With Ericsson’s goal to have optimal user experience at 5G’s 2020 release, it is very important to optimize transport protocols and techniques to manage the increasing amount of data traffic. Additionally, it will be important to manage handovers between very high speed 5G networks and older networks. Today most of the traffic is video on demand and the amount of this kind of traffic is expected to increase. Moreover, the current amount of data traffic will increase by an order of magnitude over the next few years. This thesis focuses on radio access networks and the difficulties they face in delivering high speed data traffic. This thesis analyzes one of the most used TCP protocols, CUBIC, as well as a new transport protocol developed by Aspera, called the Fast and Secure Protocol. Aspera’s FASP is a new transport protocol that promises full link utilization. FASP is built upon UDP and uses advanced round trip time measurements and queuing delay to detect the available bandwidth between two communicating hosts. This thesis project also provides methods to realize experiments to assess the limitations of transport protocols. These experiments are conducted in an environment that resembles the upcoming 5G radio access network. Results have shown that both delay and packet loss affect TCP more than we expected and that high packet loss is devastating. In contrast, Aspera’s FASP is very resistant to both delay and packet loss. These results and analysis provide a foundation upon which others can build. / Med Ericssons mål att ha optimal användarupplevelse vid släppet av 5G år 2020 är det oerhört viktigt att optimera transportprotokoll och tekniker för att hantera den ökande mängden datatrafik. En annan viktig aspekt kan vara att hantera överlämningar mellan 5G nätverk och äldre radionätverk. Idag är den största trafiken streamad video och prognoser visar att den sortens trafik bara kommer att öka. Prognoserna visar också att all trafik kommer att öka mångfaldigt de närmaste åren. Denna thesis kommer att fokusera på svårigheterna just inom radionätverk. Denna thesis kommer att analysera ett av vårt mest använda transportprotokoll CUBIC TCP, den kommer också att analysera ett helt nytt transportprotokoll utvecklat av Aspera, Fast and Secure Protocol. Aspera lovar fullt utnyttjande av den mellanliggande länken. FASP är byggt ovanpå UDP och använder avancerade tur- och returtidsmätningar för att använda all outnyttjad bandbredd. Denna thesis visar även hur man kan göra experiment för att hitta begränsningar i transportprotokoll. Alla dessa experiment kommer utförs i en miljö som efterliknar det nya 5G-nätverket. Resultatet visar att både förlora paket tillsammans med en hög fördröjning påverkar mycket mer än väntat och att frekvent förlora paket är förödande för TCP. Asperas FASP är i motsats mycket tålig mot både paketförlust och hög fördröjning. Detta resultat och denna analys lägger en grund var andra kan arbeta vidare.

In the early stages of wireless sensor networks (WSNs), low data rate traffic patterns are assumed as applications have a single purpose with simple sensing task and data packets are generated at a rate of minutes or hours. As such, most of the proposed communication protocols focus on energy efficiency rather than high throughput. Emerging high data rate applications motivate bulk data transfer protocols to achieve high throughput. The basic idea is to enable nodes to transmit a sequence of packets in burst once they obtain a medium. However, due to the low-power, low-cost nature, the transceiver used in wireless sensor networks is prone to packet loss. Especially when the transmitters are mobile, packet loss becomes worse. To reduce the energy expenditure caused by packet loss and retransmission, a burst transmission scheme is required that can adapt to the link dynamics and estimate the number of packets to transmit in burst. As the mobile node is moving within the network, it cannot always maintain a stable link with one specific stationary node. When link deterioration is constantly detected, the mobile node has to initiate a handover process to seamlessly transfer the communication to a new relay node before the current link breaks. For this reason, it is vital for a mobile node to (1) determine whether a fluctuation in link quality eventually results in a disconnection, (2) foresee potential disconnection well ahead of time and establish an alternative link before the disconnection occurs, and (3) seamlessly transfer communication to the new link. In this dissertation, we focus on dealing with burst transmission and handover issues in low power mobile wireless sensor networks. To this end, we begin with designing a novel mobility enabled testing framework as the evaluation testbed for all our remaining studies. We then perform an empirical study to investigate the link characteristics in mobile environments. Using these observations as guidelines, we propose three algorithms related to mobility that will improve network performance in terms of latency and throughput: i) Mobility Enabled Testing Framework (MobiLab). Considering the high fluctuation of link quality during mobility, protocols supporting mobile wireless sensor nodes should be rigorously tested to ensure that they produce predictable outcomes before actual deployment. Furthermore, considering the typical size of wireless sensor networks and the number of parameters that can be configured or tuned, conducting repeated and reproducible experiments can be both time consuming and costly. The conventional method for evaluating the performance of different protocols and algorithms under different network configurations is to change the source code and reprogram the testbed, which requires considerable effort. To this end, we present a mobility enabled testbed for carrying out repeated and reproducible experiments, independent of the application or protocol types which should be tested. The testbed consists of, among others, a server side control station and a client side traffic ow controller which coordinates inter- and intra-experiment activities. ii) Adaptive Burst Transmission Scheme for Dynamic Environment. Emerging high data rate applications motivate bulk data transfer protocol to achieve high throughput. The basic idea is to enable nodes to transmit a sequence of packets in burst once they obtain a medium. Due to the low-power and low-cost nature, the transceiver used in wireless sensor networks is prone to packet loss. When the transmitter is mobile, packet loss becomes even worse. The existing bulk data transfer protocols are not energy efficient since they keep their radios on even while a large number of consecutive packet losses occur. To address this challenge, we propose an adaptive burst transmission scheme (ABTS). In the design of the ABTS, we estimate the expected duration in which the quality of a specific link remains stable using the conditional distribution function of the signal-to-noise ratio (SNR) of received acknowledgment packets. We exploit the expected duration to determine the number of packets to transmit in burst and the duration of the sleeping period. iii) Kalman Filter Based Handover Triggering Algorithm (KMF). Maintaining a stable link in mobile wireless sensor network is challenging. In the design of the KMF, we utilized combined link quality metrics in physical and link layers, such as Received Signal Strength Indicator (RSSI) and packet success rate (PSR), to estimate link quality fluctuation online. Then Kalman filter is adopted to predict link dynamics ahead of time. If a predicted link quality fulfills handover trigger criterion, a handover process will be initiated to discover alternative relay nodes and establish a new link before the disconnection occurs. iv) Mobile Sender Initiated MAC Protocol (MSI-MAC). In cellular networks, mobile stations are always associated with the nearest base station through intra- and inter-cellular handover. The underlying process is that the quality of an established link is continually evaluated and handover decisions are made by resource rich base stations. In wireless sensor networks, should a seamless handover be carried out, the task has to be accomplished by energy-constraint, resource-limited, and low-power wireless sensor nodes in a distributed manner. To this end, we present MSI-MAC, a mobile sender initiated MAC protocol to enable seamless handover.

Perioperativ överrapportering associeras allt mer till säker vård, kvalitet och effektivitet. Bristande överrapportering medför en ökad risk för fördröjd- och felaktiga åtgärder, komplikationer och förlängd vårdtid för patienten. Fundamentals of Care används som teoretiskt stöd för att förstå och förklara vårdkontexten och dess påverkan på överrapporteringen samt belysa den enskilde anestesisjuksköterskans ansvar.  Syfte Syftet är att belysa anestesisjuksköterskans uppfattning om faktorer som påverkar överrapporteringen under den perioperativa vården.   Metodbeskrivning Studien är en litteraturstudie med systematisk ansats. Metoden valdes då den ansågs lämplig för att på ett systematiskt sätt skapa en överblick över publicerad forskning inom området. PEO-modellen användes som stöd vid skapandet av studiens sökstrategier och guidade vilka nyckelord från syftet som var centrala i sökprocessen. Inkluderade artiklar analyserades med hjälp av manifest kvalitativ innehållsanalys enligt Graneheim och Lundman (2004).    Resultat De faktorer som påverkar överrapportering enligt anestesisjuksköterskors uppfattning utformade tre kategorier med tillhörande subkategorier. Faktorer relaterade till arbetsmiljö, faktorer relaterade till arbetskultur och faktorer relaterade till överrapporteringens innehåll. De faktorer som påverkar överrapporteringsprocessen härleds främst till organisationen och dennes ansvar att skapa en miljö och kultur som främjar utförlig överrapportering och somliga faktorer härleds till den enskilde anestesisjuksköterskan och dennes ansvar.   Slutsats Överrapporteringen är en komplex process där fler faktorer påverkar överrapporteringens kvalitet. Kunskap gällande vilka faktorer som påverkar överrapportering skapar medvetenhet, belyser förbättringsområden inom perioperativ överrapportering vilket bidrar till säker vård. / Background  Handover in perioperative care is increasingly associated with safe care, quality and efficiency.  Lack of handover entails an increased risk of delayed and incorrect measures, complications and extended care time for the patient. Fundamentals of care is used as theoretical support to understand and explain the care context and its impact on the handover as well as highlight the responsibility of the individual nurse anesthetist.    Aim   The purpose is to investigate the anesthesia nurse's perception of factors that influence handovers during perioperative care.     Methods  The study is a systematic review. The method was chosen as it was considered suitable for overview of published research in the field. The PEO model was used to design the study's search strategies and guided keywords was also central to the search process. 18 articles were analyzed using manifest qualitative content analysis according to Graneheim and Lundman (2004).     Results  The factors that influence the handover process according to the perception of anesthesia nurses formed three categories with associated subcategories. Factors related to work environment, factors related to work culture and factors related to the content of the handover. Factors that affect the handover process are mainly derived from the organization and its ability to create an environment that promotes detailed handover. Further some factors are derived from the individual nurse anesthetists and their responsibilities.    Conclusion  Handover is a complex process where several factors might affect the quality of the process. Knowledge regarding which factors that influence the handover process creates awareness, highlights areas for improvement within peri-operative handover and thereby contributes to safe care.

Inter-Cell Interference (ICI) will be one of main problems for degrading the performance of future wireless networks at cell edge. This adverse situation will become worst in the presence of dense deployment of micro and macro cells. In this context, the Coordinated Multi-Point (CoMP) technique was introduced to mitigate ICI in Next Generation Wireless Networks (NGWN) and increase their network performance at cell edge. Even though the CoMP technique provides satisfactory solutions of various problems at cell edge, nevertheless existing CoMP handover schemes do not prevent unnecessary handover initialisation decisions and never discuss the drawbacks of CoMP handover technique such as excessive feedback and resource sharing among UEs. In this research, new CoMP-based handover schemes are proposed in order to minimise unnecessary handover decisions at cell edge and determine solution of drawbacks of CoMP technique in conjunction with signal measurements such as Reference Signal Received Power (RSRP) and Received Signal Received Quality (RSRQ). A combination of calculations of RSRP and RSRQ facilitate a credible decision making process of CoMP mode and handover mode at cell edge. Typical numerical experiments indicate that by triggering the CoMP mode along with solutions of drawbacks, the overall network performance is constantly increase as the number of unnecessary handovers is progressively reduced.

Interhospitala överföringar har ökat de senaste åren och tidigare forskning har fokuserat på transportfasen utifrån olika perspektiv. Det saknas däremot forskning kring intensivvårdssjuksköterskans upplevelse av att ta emot och vårda patienter efter interhospital överföring, därför valde vi att fokusera på detta ämne. Syftet med studien är att beskriva intensivvårdssjuksköterskans upplevelser av vårdandet av patienter efter en interhospital överföring. En kvalitativ intervjustudie genomfördes. Nio specialistsjuksköterskor inom intensivvård med erfarenhet av att vårda patienter efter interhospitala överföringar intervjuades. Dataanalysen är baserad på kvalitativ innehållsanalys och resulterade i åtta subteman och tre teman: Upplevelse av kontroll, Upplevelse av ambivalens kring överföringar, Upplevelse av samhörighet med andra. Det upplevs positivt att ta emot och vårda patienter efter interhospital transport när det finns möjlighet till förberedelse, både praktiskt och mentalt. Samma känsla infinner sig när mötet med patienten och anhöriga blir bra och när samarbetet på avdelningen och mellan enheterna är tillfredställande. Dock upplevs viss stress om det finns brister i dokumentation och informationsöverföring eller om mottagandet av patienten och dess närstående känns otillräckligt. Resultatet illustrerar komplexiteten av mottagandet efter överföring och betonar vikten av en bra överlämning. Utvecklingsområden finns såsom enhetliga journalsystem mellan regioner och att undvika interhospitala överföringar på grund av resursbrist. / Interhospital transfers have increased in number over the last years and at this point there is a good amount of research focussed on the transport phase of transfers that even includes different perspectives. There is, however, a lack of research concerned with the aftermath of a patient transfer such as taking over and caring for the patient. We therefore decided to make this the focus of our study. The aim of this study was to investigate the experience of critical nurses of caring for patients after interhospital transfer. We conducted a qualitative interview study where we interviewed nine critical care nurses from two mid-level general intensive care units. Data analysis was performed using qualitative content analysis. This resulted in 8 sub-themes and 3 main themes: Experience of control, Ambivalence regarding transfers and Experiencing fellowship. The result demonstrates that critical care nurses have a positive experience of receiving and caring for patients after interhospital transfer given that they had to opportunity to be mentally and practically prepared. Meeting the patient and their family members also generates a positive experience when the cooperation and information transfer between units has been satisfactory. Critical care nurses experience stress when they perceive threats to patient safety such as incomplete transfer of information or documentation or when the encounter with the patient and their family members was marked by problems. The result shows the complexity of taking over patients after transfer and the importance of a high-quality patient handover. Areas of improvement for transfers are seen by introducing a unified national medical record system and avoiding interhospital transfers due to lack of resources.

Den prehospitala vården är en viktig del av den svenska sjukvården, vårdprocessen innefattar all vård patient får utanför sjukhus. Den prehospitala vårdens kvalitet varierar hos olika landsting beroende på deras tekniska utrustningar och arbetsmetoder. Detta arbete utreder hur Region Kronoberg (RK) och Stockholms Läns Landsting (SLL) hanterar IT- och informationssäkerhet inom den prehospitala vården, då framförallt inom ambulanssjukvården.   Arbetet har utförts via litteraturstudie kring lagar och riktlinjer som påverkar den prehospitala vården och sedan utfördes intervjuer för att finna hur RK och SLL hanterar patientjournaler.   Arbetet visar att RK och SLL har jobbat olika länge med att digitalisera den prehospitala vårdprocessen, men att de idag använder lika säkra arbetsmetoder. Anledningen till detta är att bådas lösningar grundas i användandet av det säkra nätverket Sjunet. Vidare visade det sig att RK och SLL har olika grundförutsättningar för journalåtkomst. Avslutningsvis finner detta arbete inga säkerhetsrisker i anslutningen till de digitala journalsystemen, men att användandet av mobila enheter som lagrar journal utgör en säkerhetsrisk. / Prehospital care is an important part of the Swedish health system, the care process is dedicated to any kind of emergency out-of-hospital acute medical care. The quality of prehospital care varies between different counties, depending on their technical equipment and work methods. This essay investigates how Region Kronoberg (RK) and Stockholm’s County Council (SLL) have dealt with IT- and information security questions concerning prehospital care.   The essay is conducted by collecting laws and guidelines related to IT-security. Interviews were later on conducted with intention to collect information about RK’s and SLL’s definition of accessibility and communication of patient journals   This essay shows that RK and SLL begun digitizing their prehospital care at different times, but that they are as in now able to use equally safe methods for dealing with journals. The reason behind this is that they both root their solutions in the secluded network Sjunet. It is further concluded that SLL and RK have different prerequisites for journal access. Lastly, we could conclude that the greatest security risk is not associated with the connection between hardware, but rather misplacing any hardware containing delicate information.

With advancements in the mobile network architecture, from the Fourth Generation to the Fifth Generation, a vast number of new use cases becomes available. Many use cases require cloud-based services, where a service is deployed close to the user. For a user to communicate with a service, it connects to the mobile network base station, Fifth Generation Core network and then to the service. When the user changes physical location, the mobile network and the service must apply mobility techniques. This is to prevent tromboned traffic and provide low latency between user and service. When a handover occurs, so that a user’s attachment point to the mobile network is changed from the one base station to another and the User Plane Function changes, the cloud-based service may have to seamlessly move from one cloud to another as well. In this thesis, a Service mobility framework is proposed and implemented, which enables service live migration between edge clouds and it provides simple RESTful APIs. The evaluation of the framework shows that the proposed implementation adds low delays to the total migration time and the service downtime is also shown to be low in the case of video streaming with no service interruption. / Med framsteg i det mobila nätverkets arkitektur, sett från den Fjärde Generationen till den Femte Generationen, så blir nya användningsområden tillgängliga. Bland de nya användningsområdena inkluderas molnbaserade tjänster, där tjänster är placerade nära användare, dessutom har vissa områden behov av dessa molnbaserade tjänster. För att en användare ska kunna kommunicera med en tjänst så måste den först ansluta till det mobila nätverkets basstationer och sedan till Femte Generationens kärnnätverk, för att sedan kunna kommunicera med tjänsten. När användaren förflyttar sig från en plats till en annan, så måste det mobila nätverket och tjänsten tillämpa rörlighetstekniker, som förflyttning av tjänsten. Förflyttningen är för att förhindra trombonerad trafik och att förse låg latens mellan användare och tjänst. När en överlämning sker, d.v.s att en användares kopplingspunkt till det mobila nätverket ändras, från en basstation till en annan, och att User Plane Function ändras, så kan även den molnbaserade tjänsten förflytta sig sömlöst från ett moln till ett annat. I denna avhandling presenteras ett tjänströrlighetsramverk som möjliggör tjänströrlighet mellan moln och erbjuder enkla RESTfulla API:er. Evaluering av ramverket visar att implementationen bidrar med låga fördröjningar till den totala migrations tiden samt att tjänster med videoströmming har lågt driftstopp utan tjänstavbrott.

Mobile computing is becoming increasingly important, due to the rise in the number of portable computers and the desire to have continuous network connectivity to the Internet, irrespective of the physical location of the node. We have also seen a steady growth of the market for wireless communication devices. Such devices can only have the effect of increasing the options for making connections to the global Internet. The Internet infrastructure is built on top of a collection of protocols called the TCP/IP protocol suite. Transmission Control Protocol (TCP) and Internet Protocol (IP) are the core protocols in this suite. There are currently two standards: one to support the current IPv4 and one for the upcoming IPv6 [1]. IP requires the location of any node connected to the Internet to be uniquely identified by an assigned IP address. This raises one of the most important issues in mobility because, when a node moves to another physical location, it has to change its IP address. However, the higher-level protocols require the IP address of a node to be fixed for identifying connections. The Mobile Internet Protocol (Mobile IP) is an extension to the Internet Protocol proposed by the Internet Engineering Task Force (IETF) that addresses this issue. It enables mobile devices to stay connected to the Internet regardless of their locations, without changing their IP addresses and, therefore, an ongoing IP session will not be interrupted [2, 3, 4]. More precisely, Mobile IP is a standard protocol that builds on the Internet Protocol by making mobility transparent to applications and higher-level protocols like TCP. However, before Mobile IP can be broadly deployed, there are still several technical barriers, such as long handover periods and packet loss that have to be overcome, in addition to other technical obstacles, including handover performance, security issues and routing efficiency [7]. This study presents an investigation into developing new handover mechanisms based on link layer information in Mobile IP and fast handover in Mobile IPv6 environments. The main goal of the developed mechanisms is to improve the overall IP mobility performance by reducing packet loss, minimizing signalling overheads and reducing the handover processing time. These models include the development of a cross-layer handover scheme using link layer information and Mobile Node (MN) location information to improve the performance of the communication system by reducing transmission delay, packet loss and registration signalling overheads. Finally, the new schemes are developed, tested and validated through a set of experiments to demonstrate the relative merits and capabilities of these schemes.