184 research outputs found

    Emergency TeleOrthoPaedics m-health system for wireless communication links

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    For the first time, a complete wireless and mobile emergency TeleOrthoPaedics system with field trials and expert opinion is presented. The system enables doctors in a remote area to obtain a second opinion from doctors in the hospital using secured wireless telecommunication networks. Doctors can exchange securely medical images and video as well as other important data, and thus perform remote consultations, fast and accurately using a user friendly interface, via a reliable and secure telemedicine system of low cost. The quality of the transmitted compressed (JPEG2000) images was measured using different metrics and doctors opinions. The results have shown that all metrics were within acceptable limits. The performance of the system was evaluated successfully under different wireless communication links based on real data

    SECURITY MEASUREMENT FOR LTE/SAE NETWORK DURING SINGLE RADIO VOICE CALL CONTINUITY (SRVCC).

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    Voice has significant place in mobile communication networks. Though data applications have extensively gained in importance over the years but voice is still a major source of revenue for mobile operators. It is obvious that voice will remain an important application even in the era of Long Term Evolution (LTE). Basically LTE is an all-IP data-only transport technology using packet switching. Therefore, it introduces challenges to satisfy quality of service expectations for circuit-switched mobile telephony and SMS for LTE capable smartphones, while being served on the LTE network. Since 2013, mobile operators have been busy deploying Voice Over LTE (VoLTE). They are relying on a VoLTE technology called Single Radio Voice Call Continuity (SRVCC) for seamless handover between packet-switch domain to circuit-switch domain or vice versa. The aim of thesis is to review and identify the security measurement during SRVCC and verify test data for ciphering and integrity algorithm.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

    SECURITY MEASUREMENT FOR LTE/SAE NETWORK DURING SINGLE RADIO VOICE CALL CONTINUITY (SRVCC).

    Get PDF
    Voice has significant place in mobile communication networks. Though data applications have extensively gained in importance over the years but voice is still a major source of revenue for mobile operators. It is obvious that voice will remain an important application even in the era of Long Term Evolution (LTE). Basically LTE is an all-IP data-only transport technology using packet switching. Therefore, it introduces challenges to satisfy quality of service expectations for circuit-switched mobile telephony and SMS for LTE capable smartphones, while being served on the LTE network. Since 2013, mobile operators have been busy deploying Voice Over LTE (VoLTE). They are relying on a VoLTE technology called Single Radio Voice Call Continuity (SRVCC) for seamless handover between packet-switch domain to circuit-switch domain or vice versa. The aim of thesis is to review and identify the security measurement during SRVCC and verify test data for ciphering and integrity algorithm.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

    SECURITY AND PRIVACY ISSUES IN MOBILE NETWORKS, DIFFICULTIES AND SOLUTIONS

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    Mobile communication is playing a vital role in the daily life for the last two decades; in turn its fields gained the research attention, which led to the introduction of new technologies, services and applications. These new added facilities aimed to ease the connectivity and reachability; on the other hand, many security and privacy concerns were not taken into consideration. This opened the door for the malicious activities to threaten the deployed systems and caused vulnerabilities for users, translated in the loss of valuable data and major privacy invasions. Recently, many attempts have been carried out to handle these concerns, such as improving systems’ security and implementing different privacy enhancing mechanisms. This research addresses these problems and provides a mean to preserve privacy in particular. In this research, a detailed description and analysis of the current security and privacy situation in the deployed systems is given. As a result, the existing shortages within these systems are pointed out, to be mitigated in development. Finally a privacy preserving prototype model is proposed. This research has been conducted as an extensive literature review about the most relevant references and researches in the field, using the descriptive and evaluative research methodologies. The main security models, parameters, modules and protocols are presented, also a detailed description of privacy and its related arguments, dimensions and factors is given. The findings include that mobile networks’ security along with users are vulnerable due to the weaknesses of the key exchange procedures, the difficulties that face possession, repudiation, standardization, compatibility drawbacks and lack of configurability. It also includes the need to implement new mechanisms to protect security and preserve privacy, which include public key cryptography, HIP servers, IPSec, TLS, NAT and DTLS-SRTP. Last but not least, it shows that privacy is not absolute and it has many conflicts, also privacy requires sophisticated systems, which increase the load and cost of the system.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

    Performance evaluation of user mobility on QoS classes in a 3G network

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    The popularity of IP services is increasing and the demand for managing traffic with different QoS classes has become more challenging. The stability of the system is affected by the rate of voice traffic. Mobility allows users to be connected at all time where handover may occur as it is not always possible to be connected to the same base station. Mobility and handover cause severe interference, which affects overall throughput and capacity of the system. The system requires greater capacity with more coverage area. This study deals with the impact of user mobility on voice quality in IP based application in a 3G Network. The aim is to improve the system performance in mixed traffic environment. A mathematical model is used to analyse the impact of using different type of coder on packet end-to-end delay and packet loss. The simulation results indicate that types of coder affect the system performance. Application of scheduling based on weight and load balancing technique can improve the system performance. The deployment of scheduling based on weight and a load balancing technique have been investigated to reduce the end-to-end delay and to improve overall performance in mixed traffic environment. The results under different conditions are analysed and it is found that by applying scheduling scheme, the quality of voice communication can be improved. In addition, load balancing technique can be used to improve the performance of the system. Apart from the decrease in delay, the technique can increase the capacity of the system and the overall stability of the system can be further improved. Finally, network security is another important aspect of network administration. Security policies have to be defined and implemented so that critical sections of the network are protected against unwarranted traffic or unauthorized personnel. The impact of implementing IPSec has been tested for voice communication over IP in a 3G network. Implementing the security protocol does not significantly degrade the performance of the system.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Técnicas de segurança para a internet das coisas

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    Mestrado em Engenharia de Computadores e TelemáticaIoT assume que dispositivos limitados, tanto em capacidades computacionais como em energia disponível, façam parte da sua infraestrutura. Dispositivos esses que apresentam menos capacidades e mecanismos de defesa do que as máquinas de uso geral. É imperativo aplicar segurança nesses dispositivos e nas suas comunicações de maneira a prepará-los para as ameaças da Internet e alcançar uma verdadeira e segura Internet das Coisas, em concordância com as visões atuais para o futuro. Esta dissertação pretende ser um pequeno passo nesse sentido, apresentando alternativas para proteger as comunicações de dispositivos restritos numa perspetiva de performance assim como avaliar o desempenho e a ocupação de recursos por parte de primitivas criptográficas quando são aplicadas em dispositivos reais. Dado que a segurança em diversas ocasiões tem de se sujeitar aos recursos deixados após a implementação de funcionalidades, foi colocada uma implementação de exposição de funcionalidades, recorrendo ao uso de CoAP, num dispositivo fabricado com intenção de ser usado em IoT e avaliada de acordo com a sua ocupação de recursos.IoT comprehends devices constrained in both computational capabilities and available energy to be a part of its infrastructure. Devices which also present less defense capabilities and mechanisms than general purpose machines. It’s imperative to secure such devices and their communications in order to prepare them for the Internet menaces and achieve a true and secure Internet of Things compliant with today’s future visions. This dissertation intends to be a small step towards such future by presenting alternatives to protect constrained device’s communications in a performance related perspective as well as benchmarks and evaluation of resources used by cryptographic primitives when implemented on real devices. Due to security being on multiple occasions subjected to the resources available only after functionalities implementation, a minimalist implementation of functionalities exposure through the use of CoAP was also deployed in an IoT intended device and assessed according to resource overhead

    Performance analysis of mobile networks under signalling storms

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    There are numerous security challenges in cellular mobile networks, many of which originate from the Internet world. One of these challenges is to answer the problem with increasing rate of signalling messages produced by smart devices. In particular, many services in the Internet are provided through mobile applications in an unobstructed manner, such that users get an always connected feeling. These services, which usually come from instant messaging, advertising and social networking areas, impose significant signalling loads on mobile networks by frequent exchange of control data in the background. Such services and applications could be built intentionally or unintentionally, and result in denial of service attacks known as signalling attacks or storms. Negative consequences, among others, include degradations of mobile network’s services, partial or complete net- work failures, increased battery consumption for infected mobile terminals. This thesis examines the influence of signalling storms on different mobile technologies, and proposes defensive mechanisms. More specifically, using stochastic modelling techniques, this thesis first presents a model of the vulnerability in a single 3G UMTS mobile terminal, and studies the influence of the system’s internal parameters on stability under a signalling storm. Further on, it presents a queueing network model of the radio access part of 3G UMTS and examines the effect of the radio resource control (RRC) inactivity timers. In presence of an attack, the proposed dynamic setting of the timers manage to lower the signalling load in the network and to increase the threshold above which a network failure could happen. Further on, the network model is upgraded into a more generic and detailed model, represent different generations of mobile technologies. It is than used to compare technologies with dedicated and shared organisation of resource allocation, referred to as traditional and contemporary networks, using performance metrics such as: signalling and communication delay, blocking probability, signalling load on the network’s nodes, bandwidth holding time, etc. Finally, based on the carried analysis, two mechanisms are proposed for detection of storms in real time, based on counting of same-type bandwidth allocations, and usage of allocated bandwidth. The mechanisms are evaluated using discrete event simulation in 3G UMTS, and experiments are done combining the detectors with a simple attack mitigation approach.Open Acces
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