Ces cinquante dernières annéees, les ordinateurs ont occupé une place toujours plus importante dans notre vie quotidienne. On les retrouve aujourd’hui présents dans de nombreuses applications, sous forme de systèmes enfouis. Ces applications sont parfois critiques, dans la mesure où toute défaillance du système informatique peut avoir des conséquences catastrophiques, tant sur le plan humain que sur le plan économique. <p>Nous pensons par exemple aux systèmes informatiques qui contrôlent les appareils médicaux ou certains systèmes vitaux (comme les freins) des véhicules automobiles. <p>Afin d’assurer la correction de ces systèmes informatiques, différentes techniques de vérification Assistée par Ordinateur ont été proposées, durant les trois dernières <p>décennies principalement. Ces techniques reposent sur un principe commun: donner une description formelle tant du système que de la propriété qu’il doit respecter, et appliquer une méthode automatique pour prouver que le système respecte la propriété. <p>Parmi les principaux modèles aptes à décrire formellement des systèmes informatiques, la classe des systèmes de transition bien structurés [ACJT96, FS01] occupe une place importante, et ce, pour deux raisons essentielles. Tout d’abord, cette classe généralise plusieurs autres classes bien étudiées et utiles de modèles à espace <p>d’états infini, comme les réseaux de Petri [Pet62](et leurs extensions monotones [Cia94, FGRVB06]) ou les systèmes communiquant par canaux FIFO avec pertes [AJ93]. Ensuite, des problèmes intéressants peuvent être résolus algorithmiquement sur cette classe. Parmi ces problèmes, on trouve le probléme de couverture, auquel certaines propriétés intéressantes de sûreté peuvent être réduites. <p>Dans la première partie de cette thèse, nous nous intéressons au problème de couverture. Jusqu’à présent, le seul algorithme général (c’est-à-dire applicable à n’importe quel système bien structuré) pour résoudre ce problème était un algorithme dit en arrière [ACJT96] car il calcule itérativement tous les états potentiellement non-sûrs et vérifie si l’état initial du système en fait partie. Nous proposons Expand, Enlarge and Check, le premier algorithme en avant pour résoudre le problème de couverture, qui calcule les états potentiellement accessibles du système et vérifie si certains d’entre eux sont non-sûrs. Cette approche est plus efficace en pratique, comme le montrent nos expériences. Nous présentons également des techniques permettant d’accroître l’efficacité de notre méthode dans le cas où nous analysons des réseaux de Petri (ou <p>une de leurs extensions monotones), ou bien des systèmes communiquant par canaux FIFO avec pertes. Enfin, nous nous intéressons au calcul de l’ensemble de couverture pour les réseaux de Petri, un objet mathématique permettant notamment de résoudre le problème de couverture. Nous étudions l’algorithme de Karp & Miller [KM69], une solution classique pour calculer cet ensemble. Nous montrons qu’une optimisation de cet algorithme présenté dans [Fin91] est fausse, et nous proposons une autre solution totalement neuve, et plus efficace que la solution de Karp & Miller. <p>Dans la seconde partie de la thèse, nous nous intéressons aux pouvoirs d’expression des systèmes bien structurés, tant en terme de mots infinis que de mots finis. Le pouvoir d’expression d’une classe de systèmes est, en quelque sorte, une mesure de la diversité des comportements que les modèles de cette classe peuvent représenter. En ce qui concerne les mots infinis, nous étudions les pouvoirs d’expression des réseaux de Petri et de deux de leurs extensions (les réseaux de Petri avec arcs non-bloquants et les réseaux de Petri avec arcs de transfert). Nous montrons qu’il existe une hiérarchie stricte entre ces différents pouvoirs d’expression. Nous obtenons également des résultats partiels concernant le pouvoir d’expression des réseaux de Petri avec arcs de réinitialisation. En ce qui concerne les mots finis, nous introduisons la classe des langages bien structurés, qui sont des langages acceptés par des systèmes de transition bien structurés étiquettés, où l’ensemble des états accepteurs est clos par le haut. Nous prouvons trois lemmes de pompage concernant ces langages. Ceux-ci nous permettent de réobtenir facilement des résultats classiques de la littérature, ainsi que plusieurs nouveaux résultats. En particulier, nous prouvons, comme dans le cas des mots infinis, qu’il existe une hiérarchie stricte entre les pouvoirs d’expression des extensions des réseaux de Petri considérées. / Doctorat en sciences, Spécialisation Informatique / info:eu-repo/semantics/nonPublished

The thesis is focused on the Czech act no. 181/2014 Sb., on cyber security and subsequent regulations, introduces origin and importance of act, defines the state administration´s office which identifies important information systems according to regulations, and subsequently thesis detailed analyses act and regulation on cyber security in relation to the defined state administration´s office. Keynote of this thesis is show the real application of identified obligations of the act and regulation to the defined state administration´s office, especially a design, implementation and management of organizational and technical security measures, including the evaluation of real impact on information security. To achieve the set goals author of this thesis uses the analysis of legislation, and draws own conclusions from author´s position of a security technologist who actively participated in the design security policy, and implementation and management of security tools. The benefit of this thesis is complex overview of the security employees work at defined state administration´s office, overview of the real fulfilment obligations of the act and regulation of cybernetic security, and ultimately this thesis brings ideas for further development of technical security tools. This thesis can brings benefit to other important information systems administrators as a set of processes, proposals and recommendation for their own information security management system. This thesis is structurally divided into four main parts. The first theoretical part introduces origin, importance and impact of the act on state and private organizations. The second analytical part analyses act and subsequent regulations in relation to the defined state administration´s office. The third practical part shows the real application of organizational and technical security measures. The fourth last part evaluates the real impact of measures on information security.

This study researches the varying threats that emanate from terrorists who carry their activity into the online arena. It examines several elements of this threat, including virtual to virtual attacks and threats to critical infrastructure that can be traced to online sources. It then reports on the methods that terrorists employ in using information technology such as the internet for propaganda and other communication purposes. It discusses how the United States government has responded to these problems, and concludes with recommendations for best practices.

The purpose of this project is to design and create a system that can be used by a wide variety of groups who do projects. The system created has been specifically tailored for a medium-level company that has employees in different locations and levels, and also has customers for whom they do projects.

This dissertation focuses on the phenomenon of copper cable theft within the Gauteng Province of South Africa. Data was collected from literature sources as well as from security professionals combating copper theft. There are five primary objectives in this research: 1. To explore and to describe the extent and the impact of copper cable theft. 2. To gain insight into the profile and the modus operandi of the offender. 3. To evaluate current intervention measures used to combat the copper cable theft. 4. To describe the general factors limiting the success of combating copper cable theft. 5. To recommend probable intervention measures with which to combat copper cable theft. Semi-structured interviews were conducted with responsible security officials of victim stakeholder groups in Gauteng. It was established that copper cable theft is currently a very serious crime that deserves both attention and quick intervention before it does irreparable damage to the utility infrastructure of Gauteng, in particular, and in fact to all these infrastructures in South Africa. / Criminology and Security Science / M.A. (Criminology)

The adoption of digital health technologies has dramatically changed the healthcare sector landscape and thus generates new opportunities to collect, capture, store, access and retrieve electronic personal health information (ePHI). With the introduction of digital health technologies and the digitisation of health data, an increasing number of hospitals and peripheral health facilities across the globe are transitioning from a paper-based environment to an electronic or paper-light environment. However, the growing use of digital health technologies within healthcare facilities has caused ePHI to be exposed to a variety of threats such as cyber security threats, human-related threats, technological threats and environmental threats. These threats have the potential to cause harm to hospital systems and severely compromise the integrity and confidentiality of ePHI. Because of the growing number of security threats, many hospitals, both private and public, are struggling to secure ePHI due to a lack of robust data security plans, systems and security control measures. The purpose of this study was to explore the security of electronic personal health information in a public hospital in South Africa. The study was underpinned by the interpretivism paradigm with qualitative data collected through semi-structured interviews with purposively selected IT technicians, network controllers’, administrative clerks and records management clerks, and triangulated with document and system analysis. Audio-recorded interviews were transcribed verbatim. Data was coded and analysed using ATLAS.ti, version 8 software, to generate themes and codes within the data, from which findings were derived. The key results revealed that the public hospital is witnessing a deluge of sophisticated cyber threats such as worm viruses, Trojan horses and shortcut viruses. This is compounded by technological threats such as power and system failure, network connection failure, obsolete computers and operating systems, and outdated hospital systems. However, defensive security measures such as data encryption, windows firewall, antivirus software and security audit log system exist in the public hospital for securing and protecting ePHI against threats and breaches. The study recommended the need to implement Intrusion Protection System (IPS), and constantly update the Windows firewall and antivirus program to protect hospital computers and networks against newly released viruses and other malicious codes. In addition to the use of password and username to control access to ePHI in the public hospital, the study recommends that the hospital should put in place authentication mechanisms such as biometric system and Radio Frequency Identification (RFID) system restrict access to ePHI, as well as to upgrade hospital computers and the Patient Administration and Billing (PAAB) System. In the absence of security policy, there is a need for the hospital to put in place a clear written security policy aimed at protecting ePHI. The study concluded that healthcare organisations should upgrade the security of their information systems to protect ePHI stored in databases against unauthorised access, malicious codes and other cyber-attacks. / Information Science / M. Inf. (Information Security)

Effective and satisfactory security service is critical to private security officers (PSOs) working in the private, state-owned and public sectors as it plays a pivotal role in improving organisational productivity and helps to promote good working relationships. When PSOs project poor attitudes, clients are seriously affected by such negative behaviour and the level of service rendered will eventually deteriorate. This study sought to understand and explore the factors that contributed to unsatisfactory services rendered by PSOs at GPW in Tshwane. The researcher utilised a nonexperimental quantitative research approach and a self-administered questionnaire survey was used to collect data. Data collected was analysed and interpreted using quantitative methods and procedures. The findings emanating from the research revealed that the levels of service rendered by PSOs at GPW in Tshwane was ineffective and unsatisfactory and various factors contributed to ineffective service delivery. Several recommendations are proposed to improve the level of service rendered by PSOs. / Criminology and Security Science / M. Tech. (Security Management)

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / A wireless sensor network consists of lightweight nodes with a limited power source. They can be used in a variety of environments, especially in environments for which it is impossible to utilize a wired network. They are easy/fast to deploy. Nodes collect data and send it to a processing center (base station) to be analyzed, in order to detect an event and/or determine information/characteristics of the environment. The challenges for securing a sensor network are numerous. Nodes in this network have a limited amount of power, therefore they could be faulty because of a lack of battery power and broadcast faulty information to the network. Moreover, nodes in this network could be prone to different attacks from an adversary who tries to eavesdrop, modify or repeat the data which is collected by other nodes. Nodes may be mobile. There is no possibility of having a fixed infrastructure. Because of the importance of extracting information from the data collected by the sensors in the network there needs to be some level of security to provide trustworthy information. The goal of this thesis is to organize part of the network in an energy efficient manner in order to produce a suitable amount of integrity/security. By making nodes monitor each other in small organized clusters we increase security with a minimal energy cost. To increase the security of the network we use cryptographic techniques such as: public/ private key, manufacturer signature, cluster signature, etc. In addition, nodes monitor each other's activity in the network, we call it a "neighborhood watch" In this case, if a node does not forward data, or modifies it, and other nodes which are in their transmission range can send a claim against that node.

<p dir="ltr">With the ability to connect to networks and send and receive data, Internet of Things (IoT) devices involve associated security risks and threats, for a given environment. These threats are even more of a concern in a Smart Home network, where there is a lack of a dedicated security IT team, unlike a corporate environment. While efficient user interface(UI) and ease of use is at the front and center of IoT devices within Smart Home which enables its wider adoption, often security and privacy have been an afterthought and haven’t kept pace when needed. Therefore, a unsafe possibility exists where malicious actors could exploit vulnerable devices in a domestic home environment.</p><p dir="ltr">This thesis involves a detailed study of the cybersecurity for a Smart Home and also examines the various types of cyberthreats encountered, such as DDoS, Man-In-Middle, Ransomware, etc. that IoT devices face. Given, IoT devices are commonplace in most home automation scenarios, its crucially important to detect intrusions and unauthorized access. Privacy issues are also involved making this an even more pertinent topic. Towards this, various state of the art industry standard tools, such as Nmap, Nessus, Metasploit, etc. were used to gather data on a Smart Home environment to analyze their impacts to detect security vulnerabilities and risks to a Smart Home. Results from the research indicated various vulnerabilities, such as open ports, password vulnerabilities, SSL certificate anomalies and others that exist in many cases, and how precautions when taken in timely manner can help alleviate and bring down those risks.</p><p dir="ltr">Also, an IoT monitoring dashboard was developed based on open-source tools, which helps visualize threats and emphasize the importance of monitoring. The IoT dashboard showed how to raise alerts and alarms based on specific threat conditions or events. In addition, currently available cybersecurity regulations, standards, and guidelines were also examined that can help safeguard against threats to commonly used IoT devices in a Smart Home. It is hoped that the research carried out in this dissertation can help maintain safe and secure Smart Homes and provide direction for future work in the area of Smart Home Cybersecurity.</p>