No abstract

No abstract

The subject of Key Management in Wireless Sensor Networks has gained increased attention from the security community around the world in the last years. Several proposals were made concerning the peculiarities of resource constrains inherent to sensor devices. One of the most accepted proposals is based on random distribution of keys among the sensor nodes, which was followed by some variants in order to increase its security. In this paper we introduce the mathematical concepts behind this class of proposals through a step-by-step mathematical analysis. This leads to some practical concerns about its applicability to real world applications where the technological constrains strictly compromise the mathematical theoretical models. We demonstrate that the number of communication links needed to assure near 100% network connectivity, is in fact, impractical in nowadays applications.

The aim of this paper is to introduce and improve the functionality and reliability of the indoor glass-break detectors for the security application. The most vulnerable part of the house security are the windows which are fragile and very easy to overcome. The glass-break or shock detector are generally used to detect the potential intruder by vibration which is spreading through the glass. The alarm is triggered when a threshold level of the vibration is exceeded. However, the further information of the intrusion is missing. The goal of this paper is a design of a glass-break detector based on the accelerometer which can also detect the vibration in the glass panels with higher accuracy. The main advantage of the implemented accelerometer is the ability to sense several influences of the environment. The program can reliably distinguish between main influences like the rain, storm or strong wind. This function can also be used for the non-alarm application. However, the main function is still focused on the security application. The designed detector should be able to communicate with commercially made Control and Indicating Equipment via the wired connection.

The increasing aggression in the population, which is undoubtedly associated with the onset of narcissism, also entails an increase in the number of assaults in society. Of course, the number of clashes when a Weapon is used is also increasing. In most cases, these are weapons classified as weapons of category D (according to the Czech legislation), especially air guns, expansion weapons, and airsoft guns. This fact needs to be addressed, not by impulsive bans under duress, but by subjecting these weapons to the investigation, especially in the field of wounding ballistics, which answers the questions about the wounding potential of these weapons. This paper deals with one of these weapons, specifically airsoft gun with used ammunition lead shot. The depth of the shot and the size of the temporary and permanent cavity in relation to the distance were investigated, the contact distance was measured, and then the distance of 5 m.

RFID technology has established itself in many sectors of human activity, including security and access systems. Just at this context, the demands on the hardware design in terms of its electromagnetic compatibility become critical. This paper provides a description of an immunity test against the electrostatic discharge according to the standard EN 61000-4-2 that was applied to an RFID reader which was primarily intended to be applied in access systems, employing the on-board recognition of the RFID tags. It was shown that such device can be endangered by the external electrostatic pulse; the findings described in this paper may be beneficial for the developers of the hardware for the RFID devices.

Abstract. This paper provides a description of an immunity test against the electrostatic discharge according to the standard EN 61000-4-2 that was applied to an RFID reader. The RFID reader was primarily developed for access systems, employing the on-board recognition of the RFID tags. The results obtained by the test are described hereby as well as the discussion on the security of this solution. The results of this experiment are beneficial for the developers of RFID devices, as these devices are endangered by the electrostatic discharge brought by their users. The hereby described results also shown a security hole in a simple access system based on the RFID technology. Details can be found in the paper.

No abstract