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Covert and Side-Channels have been known for a long time due to their versatile forms of appearance. For nearly every technical improvement or change in technology, such channels have been (re-)created or known methods have been adapted. For example the introduction of hyperthreading technology has introduced new possibilities for covert communication between malicious processes because they can now share the arithmetic logical unit (ALU) as well as the L1 and L2 cache which enables establishing multiple covert channels. Even virtualization which is known for its isolation of multiple machines is prone to covert and side-channel attacks due to the sharing of resources. Therefore itis not surprising that cloud computing is not immune to this kind of attacks. Even more, cloud computing with multiple, possibly competing users or customers using the same shared resources may elevate the risk of unwanted communication. In such a setting the ”air gap” between physical servers and networks disappears and only the means of isolation and virtual separation serve as a barrier between adversary and victim. In the work at hand we will provide a survey on weak spots an adversary trying to exfiltrate private data from target virtual machines could exploit in a cloud environment. We will evaluate the feasibility of example attacks and point out possible mitigation solutions if they exist.
In this paper an RFID/NFC (ISO 15693 standard) based inductively powered passive SoC (system on chip) for biomedical applications is presented. A brief overview of the system design, layout techniques and verification method is dis-cussed here. The SoC includes an integrated 32 bit microcontroller, sensor interface circuit, analog to digital converter, integrated RAM, ROM and some other peripherals required for the complete passive operation. The entire chip is realized in CMOS 0.18 μm technology with a chip area of 1.52mm x 3.24 mm.
Skills, abilities and capability of our freshmen are increasingly heterogeneous, regarding age, attained levels of education and motivational aspects. Additionally, students tend to recoil from subjects dealing with mathematical backgrounds. As a result high, drop-out numbers are a huge problem in technical degree programs.
Since mechanics is based on physics and mathematics our students face enormous difficulties. To deal with them, a form of teaching and learning has been developed that is composed of the following arrangements:
1. Problems and tasks of different levels are solved during lessons. The access to theoretical issues is being developed by or rather as a result of solving these problems. By doing so, especially students with yet insufficient skills are enabled to develop their methodological skills.
2. Challenging students to independently transfer these skills on other problems is helpful. At the end of each lecture two students are selected randomly. Each of them is faced with an exercise they have to solve and present at the beginning of the next lecture. Because of small student numbers, chances are high that every student participates at least once by the end of semester. Surveys show that particularly weaker students benefit from that kind of model learning.
3. We are surrounded by mechanical issues. Given that, students are presented with “every-day-life” problems which students can apply their theoretical knowledge on. The problems are analyzed by groups of students, which leads to an enhanced and reflective perception of each and every one. Some examples are: “A broomstick in equilibrium”, “Sensitive cups”, “Transforming a roman basilica into a gothic cathedral”.
4. All lectures have been filmed by the staff of the Information Center of the Offenburg University during the previous term. Additionally to the notes taken by the students individually during the lectures, these recordings are helpful in the process of preparation and post-processing of the material. The recordings are accessible via the university’s learning management system “Moodle”.
Surveys show that students benefit from the great variety of the provided, interactive learning arrangements. It is interesting to discover that students not only take positive advantages in the lecture “mechanics 1/statics” but tend to transfer these positive experiences on other subjects.
The invention concerns a method for spectrum monitoring a given frequency band, in which the spectral power density (S(f)) within the given frequency band is determined for all noise and signal components in the frequency band and, in order to detect the presence of one or more signals within the given frequency band, it is evaluated whether the spectral power density (S(f)) exceeds a threshold value (&lgr;). According to the invention, the threshold value (&lgr;) is calculated in accordance with an estimation of a distribution density (hR(S)) for the noise component of the spectral power density (S(f)) within the given frequency band and in accordance with a predefined value for the false-alarm probability (Pfa).
The United Nations have declared 2015 as the International Year of Light (IYL2015) and light-based technologies [1]. As a main result, the public interest is focused on both the achievements and the new frontiers of optics and photonics. This opens up new perspectives in the teaching and training of optics and photonics. In the first part of the paper, the author presents the numerous anniversaries occurring in the International Year of Light 2015 together with their importance to the development of science and technology. In the second part, we report on an interactive video projection at the opening ceremony of the IYL2015 in Paris on January 19-20, 2015. Students of Offenburg University have established an interactive video projection which visualizes Twitter and Facebook messages posted with the hashtag #iyl2015 in a mapping technique. Thus, the worldwide community can be interactively part of the opening ceremony. Finally, upcoming global community projects related to optics and astronomy events are presented.
Theoretical details about optics and photonics are not common knowledge nowadays. Physicists are keen to scientifically explain ‘light,’ which has a huge impact on our lives. It is necessary to examine it from multiple perspectives and to make the knowledge accessible to the public in an interdisciplinary, scientifically well-grounded and appealing medial way. To allow an information exchange on a global scale, our project “Invisible Light” establishes a worldwide accessible platform. Its contents will not be created by a single instance, but user-generated, with the help of the global community. The article describes the infotainment portal “Invisible Light,” which stores scientific articles about light and photonics and makes them accessible worldwide. All articles are tagged with geo-coordinates, so they can be clearly identified and localized. A smartphone application is used for visualization, transmitting the information to users in real time by means of an augmented reality application. Scientific information is made accessible for a broad audience and in an attractive manner.
Alexander von Humboldt, a German scientist and explorer of the 19th century, viewed the natural world holistically and described the harmony of nature among the diversity of the physical world as a conjoining between all physical disciplines. He noted in his diary: “Everything is interconnectedness.”
The main feature of Humboldt’s pioneering work was later named “Humboldtian science”, meaning the accurate study of interconnected real phenomena in order to find a definite law and a dynamic cause.
Following Humboldt's idea of nature, an Internet edition of his works must preserve the author’s original intention, retain an awareness of all relevant works, and still adhere to the requirements of scholarly edition.
At the present time, however, the highly unconventional form of his publications has undermined the awareness and a comprehensive study of Humboldt’s works.
Digital libraries should supply dynamic links to sources, maps, images, graphs and relevant texts. New forms of interaction and synthesis between humanistic texts and scientific observation need to be created.
Information technology is the only way to do justice to the broad range of visions, descriptions and the idea of nature of Humboldt’s legacy. It finally leads to virtual research environments as an adequate concept to redesign our digital archives, not only for Humboldt’s documents, but for all interconnected data.
This article sets the focus on methods of information technology in the Humboldt Portal, which represents an ongoing research project to develop a virtual research environment on the Internet for the legacy of Alexander von Humboldt. Based on the experiences of developing and providing the Humboldt Digital Library (www.avhumboldt.net) for more than a decade, we defined a working plan to create an Internet portal for comprehensive access to Humboldt’s writings, no matter if documents are provided as PDF files, scan images or XML-TEI documents on external archives (Google Books, Internet Archive, Deutsches Textarchiv, Bibliotheque National de France). Going far beyond services of a digital library we will provide an information network with multimedia assets, which are containing objects like terms, paragraphs, data tables, scan images, or illustrations, together with correlated properties like thematic linkage to other objects, relevant keywords with optional synonyms and dynamic hyperlinks to related translations in different languages. So the Humboldt Portal can contribute to the key question, how to present interconnected data in an appropriate form using information technologies on the Web.
The aim of this research work was to develop a boiler model with few parameters required for energy planning. The showcase considered for this work was the boiler system of the energy center at Offenburg University of Applied Sciences. A grey box model of the boiler was developed systematically starting from model abstraction, simplification, model break-down and to the use of empirical correlations wherever necessary to describe the intermediate effects along with the use of information from manufacturer’s specification in order to reduce parameters. This strategy had resulted in a boiler model with only 6 parameters, namely, nominal burner capacity, water gallery capacity, air ratio, heat capacity of wall, thermal conductance on flue gas and hot water side. Most of these parameters can be obtained through the information available in the spec sheets and thus an energy planner will be able to parameterize the model with low effort. The model was validated with the monitored data of the showcase. It was tested for the start-up, shut-down behavior and the effect of storage.
Cardiac resynchronization therapy with atrioventricular and interventricular delay optimized biventricular pacing is an established therapy for symptomatic heart failure patients with prolongation of QRS duration, left bundle branch block and reduced left ventricular ejection fraction. The aim of the investigation was to evaluate right atrial, right ventricular and left ventricular electrical signals of implantable electronic cardiac devices with and without signal averaging technique with novel LabVIEW software. Electrical interatrial conduction delay and inter-ventricular conduction delay may be useful parameters to evaluate electrical atrial and ventricular desynchronization in heart failure patients.
Android is the most popular mobile operating system. Its omnipresence leads to the fact that it is also the most popular target amongst malware developers and other computer criminals. Hence, this thesis shows the security-relevant structures of Android’s system and application architecture. Furthermore, it provides laboratory exercises on various security-related issues to understand them not only theoretically but also deal with them in a practical way. In order to provide infrastructure-independent education, the exercises are based on Android Virtual Devices (AVDs).
Quarz crystal microbalances allow the monitoring of the adsorption process of mass from a liquid to their surface. The adsorbed mass can be analysed regarding to its protein content using mass spectromety. To ensure the protein identification the results of several measurements can be combined. A high content QCM-D array was developed to allow up to ten measurements parallel. The samples can be routed inside the array distributing one sample to several chips. The fluidic parts were prototyped using 3D printing. The assembled array was tight and the sample routing function could be demonstrated. A temperature controller was developed and implemented. The parameters for the PID controller were determined and the controller was shown to be able to keep the temperature constant over long time with high accuracy.
Additive Manufacturing and Reverse Engineering have increasingly been gaining in importance over the past years. This paper investigates the current status of the implementation of these new technologies in design education and also identifies current shortcomings. Then it develops two new approaches for the teaching of the necessary expertise for the design of 3D-printed components and illustrates these with case studies. First, a workshop is presented in which students gain a broad understanding for the functionalities of additive manufacturing and the creative possibilities and limits of this process, through the assembly and installation of a 3D-printer. A second new approach is the combination of reverse engineering and 3D-printing. Thereby, students learn how to deal with this complex process chain. The result of these new approaches can e.g. be seen in the design guidelines for Additive Manufacturing, which were developed by the students themselves. At the same time, the students are able to estimate opportunities and limits of both technologies. Finally, the success of the new course contents and form is reviewed by an evaluation by the students.
In addition to traditional methods in product development, the increasing availability of two new 3D digital technologies, namely digital manufacturing (3D-printing) and digitizing of surfaces (3D-scanning), offer new opportunities in product development processes today. With regard to the systematic implementation of these technologies in the education of students in the field of product development, however, only a small number of approaches exist so far. This paper explores several ways in which 3D digital technologies can productively be used in design education. The innovative aspects here include that the students assemble and install the 3D-printers themselves, and that they are introduced to an approach that combines 3D-scanning followed by 3D-printing.
In this work we provide an overview of gamification, i.e. the application of methods from game design to enrich non-gaming processes. The contribution is divided into five subsections: an introduction focusing on the progression of gamification through the hype cycle in the recent years (1), a brief introduction to gamification mechanics (1) and an overview of the state of the art in established areas (3). The focus is a discussion of more recent attempts of gamification in service and production (4). We also discuss the ethical implications (5) and the future perspectives (6) of gamified business processes. Gamification has been successfully applied in the domains education (serious games) and health (exergames) and is spreading to other areas. In recent years there have been various attempts to “gamify” business processes. While the first efforts date back as far as the collection of miles in frequent flyer programs, we will portray some of the more recent and comprehensive software-based approaches in the service industry, e.g. the gamification of processes in sales and marketing. We discuss their accomplishments as well as their social and ethical implicatio. Finally a very recent approach is presented: the application of gamification in the domain of industrial production. We discuss the special requirements in this domain and the effects on the business level and on the users. We conclude with a prognosis on the future development of gamification.
A wet-chemical treatment system for electrochemically coating flat substrates with coating material, has having a basin for receiving an electrolyte, a transporting means, by means of which the flat substrates can be transported through the electrolyte horizontally, and at least one contact element which comprises a shaft having an axis of rotation and a cylindrical circumferential surface suitable for rolling on the substrate, wherein the circumferential surface comprises at least one electrically insulated segment and at least one electrically conductive segment which can be connected to a current source in such a way that the polarity can be reversed, wherein the axis of rotation of the contact element is positioned above the surface of the electrolyte, and wherein the contact element is designed as a consumable electrode.
Systemic Constellations are a phenomenological approach to resolving personal, professional and organizational issues. They offer a way of mapping a present reality, working at the source of the hidden dynamics and moving to a resolution. This systemic approach often delivers surprising and unexpected insights while also offering the possibility to analyze and solve organizational problems. Rational analysis provides the whole picture of the problem which often turns out to be too complex for a decision making. Systemic constellations can help to simplify and clarify the situation and inform what has to happen next [8], [17]. The outcomes of systemic constellations as an additional resource for solving comprehensive technical problems have not yet been sufficiently investigated. In structural constellation work dealing with technical problems, the individuals who are involved in the problem situation are used to represent different system components, substances or fields. A moderator voices the feedback from the representatives concerning their feelings or intuitive movements, and points to possible solutions. For example, a moderator places the representatives somewhere in the room, develops a three-dimensional picture of the constellation of the analyzed situation and tries to expose the factors empowering or blocking the way towards constructive solutions [13]. This paper explores the theoretical background and practical outcomes of the systemic constellation method for technical problem solving. It presents some case study work which has been conducted in recent years, and then discusses its findings and implications. The research outlined in this paper demonstrates that the noteworthy contribution of structural constellation work for problem solving is typically the result of a combination of functional analysis and the feeling-as-information principle. The constellation work helps, at first, to reveal the subjective experiences, such as feelings, moods, emotions, and bodily sensations, and then to accept them as a source of objective information relevant to the decision making process. In accordance with the latest research [19], the use of feelings as a source of information follows the same principles as the use of any other information. This paper provides the structures of some standard templates and types of constellation work for technical problems, and discusses the preconditions for their application.
The Metering Bus, also known as M-Bus, is a European standard EN13757-3 for reading out metering devices, like electricity, water, gas, or heat meters. Although real-life M-Bus networks can reach a significant size and complexity, only very simple protocol analyzers are available to observe and maintain such networks. In order to provide developers and installers with the ability to analyze the real bus signals easily, a web-based monitoring tool for the M-Bus has been designed and implemented. Combined with a physical bus interface it allows for measuring and recording the bus signals. For this at first a circuit has been developed, which transforms the voltage and current-modulated M-Bus signals to a voltage signal that can be read by a standard ADC and processed by an MCU. The bus signals and packets are displayed using a web server, which analyzes and classifies the frame fragments. As an additional feature an oscilloscope functionality is included in order to visualize the physical signal on the bus. This paper describes the development of the read-out circuit for the Wired M-Bus and the data recovery.
In this paper, the initial multiaxial yield behavior of three different gray cast iron materials with lamellar shaped graphite inclusions is numerically investigated by means of the finite-element method. Therefore, volume elements including the real microstructure of the materials are loaded bi- and triaxially beyond macroscopic yield. The shape of the obtained yield surfaces are compared to the surfaces of four continuum models which, amongst others, are proposed in literature to describe the inelastic behavior of gray cast iron with lamellar shaped graphite inclusions. It is found that the presented continuum models and the macroscopic yield surfaces obtained with microstructure-based finite-element models deviate. Furthermore, the initial inelastic flow direction is computed at the onset of macroscopic yielding. The analysis show that the inelastic flow is normal to the yield surface.
This paper focuses on the microstructure-dependent inelastic behavior of lamellar gray cast iron. It comprises the reconstruction of three dimensional volume elements by use of the serial sectioning method for the materials GJL-150, GJL-250 and GJL-350. The obtained volume elements are prepared for the numerical analyses by means of finite-element method. In the finite-element analysis, the metallic matrix is modeled with an elastic–plastic deformation law. The graphite inclusions are modeled nonlinear elastic with a decreasing value of Young’s modulus for increasing tensile loading. Thus, the typical tension–compression asymmetry of this material class can be described. The stress–strain curves obtained with the microstructure-based finite-element models agree well with experimental curves of tension and compression tests. Besides the analysis of the whole volume element, the scatter of the stress–strain response in smaller statistical volume elements is investigated. Furthermore, numerical studies are performed to reduce computational costs.
Environmental Monitoring is an attractive application field for Wireless Sensor Network (WSN). Water Level Monitoring helps to increase the efficiency of water distribution and management. In Pakistan, the world’s largest irrigation system covers 90.000 km of channels which needs to be monitored and managed on different levels. Especially the sensor systems for the small distribution channels need to be low energy and low cost. The distribution presents a technical solution for a communication system which is developed in a research project being co-funded by German Academic Exchange Service (DAAD). The communication module is based on IEEE-802.15.4 transceivers which are enhanced through Wake-On-Radio (WOR) to combine low-energy and real-time behavior. On higher layers, IPv6 (6LoWPAN) and corresponding routing protocols like Routing Protocol for Low power and Lossy Networks (RPL) can extend range of the network. The data are stored in a database and can be viewed online via a web interface. Of course, also automatic data analysis can be performed.
Distributed Flow Control and Intelligent Data Transfer in High Performance Computing Networks
(2015)
This document contains my master thesis report, including problem definition, requirements, problem analysis, review of current state of the art, proposed solution,
designed prototype, discussions and conclusion.
During this work we propose a collaborative solution to run different types of operations in a broker-less network without relying on a central orchestrator.
Based on our requirements, we define and analyze a number of scenarios. Then we design a solution to address those scenarios using a distributed workflow management approach. We explain how we break a complicated operation into simpler parts and how we manage it in a non-blocking and distributed way. Then we show how we asynchronously launch them on the network and how we collect and aggregate results. Later on we introduce our prototype which demonstrates the proposed design.
The transformation of the building energy sector to a highly efficient, clean, decentralised and intelligent system requires innovative technologies like microscale trigeneration and thermally activated building structures (TABS) to pave the way ahead. The combination of such technologies however presents a scientific and engineering challenge. Scientific challenge in terms of developing optimal thermo-electric load management strategies based on overall energy system analysis and an engineering challenge in terms of implementing these strategies through process planning and control. Initial literature research has pointed out the need for a multiperspective analysis in a real life laboratory environment. To this effect an investigation is proposed wherein an analytical model of a microscale trigeneration system integrated with TABS will be developed and compared with a real life test-rig corresponding to building management systems. Data from the experimental analysis will be used to develop control algorithms using model predictive control for achieving the thermal comfort of occupants in the most energy efficient and grid reactive manner. The scope of this work encompasses adsorption cooling based microscale trigeneration systems and their deployment in residential and light commercial buildings.
Autonomous humanoid robots require light weight, high torque and high speed actuators to be able to walk and run. For conventional gears with a fixed gear ratio the product of torque and velocity is constant. On the other hand desired motions require maximum torque and speed. In this paper it is shown that with a variable gear ratio it is possible to vary the relation between torque and velocity. This is achieved by introducing systems of rods and levers to move the joints of our humanoid robot ”Sweaty II”. On the basis of a variable gear ratio low speed and high torque can be achieved for those joint angles, which require this motion mode, whereas high speed and low torque can be realized for those joint angles, where it is favorable for the desired motion.
The increasing number of transistors being clocked at high frequencies of modern microprocessors lead to an increasing power consumption, which calls for an active dynamic thermal management. In a research project a system environment has been developed, which includes thermal modeling of the microprocessor in the board system, a software environment to control the characteristics of the system’s timing behavior, and a modified Linux scheduler, which is enhanced with a prediction controller. Measurement results are shown for this development for a Freescale i.MX6Q quad-core microprocessor.
Transcatheter aortic valve implantation is a therapy for patients with reduced left ventricular ejection fraction and symptomatic aortic stenosis. The aim of the study was to compare the pre-and post- transcatheter aortic valve implantation procedures to determine the QRS and QT ventricular conduction times as a potential predictor of permanent pacemaker therapy requirement after transcatheter aortic valve implantation. QRS and QT ventricular conduction times were prolonged after transcatheter aortic valve implantation in heart failure patients with permanent dual chamber pacemaker therapy after transcatheter aortic valve implantation. QRS and QT ventricular conduction times may be useful parameters to evaluate the risk of post-procedural ventricular conduction block and permanent pacemaker therapy in transcatheter aortic valve implantation.
Bluetooth Low Energy extends the Bluetooth standard in version 4.0 for ultra-low energy applications through the extensive usage of low-power sleeping periods, which inherently difficult in frequency hopping technologies. This paper gives an introduction into the specifics of the Bluetooth Low Energy protocol, shows a sample implementation, where an embedded device is controlled by an Android smart phone, and shows the results of timing and current consumption measurements.
Cardiac resynchronization therapy (CRT) is an established therapy for heart failure patients and improves quality of life in patients with sinus rhythm, reduced left ventricular ejection fraction (LVEF), left bundle branch block and wide QRS duration. Since approximately sixty percent of heart failure patients have a normal QRS duration they do not benefit or respond to the CRT. Cardiac contractility modulation (CCM) releases nonexcitatoy impulses during the absolute refractory period in order to enhance the strength of the left ventricular contraction. The aim of the investigation was to evaluate differences in cardiac index between optimized and nonoptimized CRT and CCM devices versus standard values. Impedance cardiography, a noninvasive method was used to measure cardiac index (CI), a useful parameter which describes the blood volume during one minutes heart pumps related to the body surface. CRT patients indicate an increase of 39.74 percent and CCM patients an improvement of 21.89 percent more cardiac index with an optimized device.
Monitors are in the center of media productions and hold an important function as the main visual interface. Tablets and smartphones are becoming more and more important work tools in the media industry. As an extension to our lecture contents an intensive discussion of different display technologies and its applications is taking place now. The established LCD (Liquid Crystal Display) technology and the promising OLED (Organic Light Emitting Diode) technology are in the focus.
The classic LCD is currently the most important display technology. The paper will present how the students should develop sense for display technologies besides the theoretical scientific basics. The workshop focuses increasingly on the technical aspects of the display technology and has the goal of deepening the students understanding of the functionality by building simple Liquid Crystal Displays by themselves.
The authors will present their experience in the field of display technologies. A mixture of theoretical and practical lectures has the goal of a deeper understanding in the field of digital color representation and display technologies. The design and development of a suitable learning environment with the required infrastructure is crucial. The main focus of this paper is on the hands-on optics workshop “Liquid Crystal Display in the do-it-yourself”.
Security in IT systems, particularly in embedded devices like Cyber Physical Systems (CPSs), has become an important matter of concern as it is the prerequisite for ensuring privacy and safety. Among a multitude of existing security measures, the Transport Layer Security (TLS) protocol family offers mature and standardized means for establishing secure communication channels over insecure transport media. In the context of classical IT infrastructure, its security with regard to protocol and implementation attacks has been subject to extensive research. As TLS protocols find their way into embedded environments, we consider the security and robustness of implementations of these protocols specifically in the light of the peculiarities of embedded systems. We present an approach for systematically checking the security and robustness of such implementations using fuzzing techniques and differential testing. In spite of its origin in testing TLS implementations we expect our approach to likewise be applicable to implementations of other cryptographic protocols with moderate efforts.
The automatic classification of the modulation format of a detected signal is the intermediate step between signal detection and demodulation. If neither the transmitted data nor other signal parameters such as the frequency offset, phase offset and timing information are known, then automatic modulation classification (AMC) is a challenging task in radio monitoring systems. The approach of clustering algorithms is a new trend in AMC for digital modulations. A novel algorithm called `highest constellation pattern matching' is introduced to identify quadrature amplitude modulation and phase shift keying signals. The obtained simulation and measurement results outperform the existing algorithms for AMC based on clustering. Finally, it is shown that the proposed algorithm works in a real monitoring environment.
In many scientific studies lens experiments are part of the curriculum. The conducted experiments are meant to give the students a basic understanding for the laws of optics and its applications. Most of the experiments need special hardware like e.g. an optical bench, light sources, apertures and different lens types. Therefore it is not possible for the students to conduct any of the experiments outside of the university’s laboratory. Simple optical software simulators enabling the students to virtually perform lens experiments already exist, but are mostly desktop or web browser based.
Augmented Reality (AR) is a special case of mediated and mixed reality concepts, where computers are used to add, subtract or modify one’s perception of reality. As a result of the success and widespread availability of handheld mobile devices, like e.g. tablet computers and smartphones, mobile augmented reality applications are easy to use. Augmented reality can be easily used to visualize a simulated optical bench. The students can interactively modify properties like e.g. lens type, lens curvature, lens diameter, lens refractive index and the positions of the instruments in space. Light rays can be visualized and promote an additional understanding of the laws of optics. An AR application like this is ideally suited to prepare the actual laboratory sessions and/or recap the teaching content.
The authors will present their experience with handheld augmented reality applications and their possibilities for light and optic experiments without the needs for specialized optical hardware.
The overview of public key infrastructure based security approaches for vehicular communications
(2015)
Modern transport infrastructure becomes a full member of globally connected network. Leading vehicle manufacturers have already triggered development process, output of which will open a new horizon of possibilities for consumers and developers by providing a new communication entity - a car, thus enabling Car2X communications. Nevertheless some of available systems already provide certain possibilities for vehicles to communicate, most of them are considered not sufficiently secured. During last 15 years a number of big research projects funded by European Union and USA governments were started and concluded after which a set of standards were published prescribing a common architecture for Car2X and vehicles onboard communications. This work concentrates on combining inner and outer vehicular communications together with a use of Public Key Infrastructure (PKI).