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This paper is about the PROFINET communication used in industry for the purposes of communication between different elements within systems of monitoring and control of production processes. The PROFINET protocol is based on industrial Ethernet and allows the use of TCP / IP standards, which allows big business benefits during the life cycle of a manufacturing plant. Also, PROFINET is based on all the experiences with PROFIBUS, and goes a step further in its flexibility, improving performances. PROFINET enables the integration of various control equipment from the factory level to the control level. The concept of PROFINET satisfies all the requirements of industrial automation, and can be used for process automation that requires quick response time, i.e. the time below 100ms. For the purposes of other applications such as synchronized motion control, it enables a response time of less than 1 ms, and for safety applications it is possible to use PROFIsafe which is integrated into PROFINET. [ABSTRACT FROM AUTHOR]

Security of wireless computer networks was initially secured with the WEP security protocol, which relies on the RC4 encryption algorithm and the CRC algorithm to check the integrity. The basic problems of the WEP are a short initialization vector, unsafe data integrity checking, using a common key, the lack of mechanisms for management and exchange of keys, the lack of protection from the endless insertion of the same package into the network, the lack of authentication of access points and the like. The consequences of these failures are easy attacks against the WEP network, namely their complete insecurity. Therefore, the work began on the IEEE 802.11i protocol, which should radically improve the security of wireless networks. Since the development of a protocol lasted, the WPA standard was released to offset the security gap caused by the WEP. The WPA also relies on RC4 and CRC algorithms, but brings temporary keys and the MIC algorithm for data integrity. The 802.1X authentication was introduced and common keys are no longer needed, since it is possible to use an authentication server. The length of the initialization vector was increased and the vector is obtained based on the packet serial number, in order to prevent the insertion of the same packet into the network. The weakness of the WPA security mechanism is the use of a common key. WPA2 (802.11i) later appeared. Unlike the WPA mechanism that worked on old devices with the replacement of software, WPA2 requires new network devices that can perform AES encryption. AES replaces the RC4 algorithm and delivers much greater security. Data integrity is protected by encryption. Despite progress, there are still weaknesses in wireless networks. Attacks for denial of service are possible as well as spoofing package headers attacks. For now, it is not advisable to use wireless networks in environments where unreliability and unavailability are not tolerated. [ABSTRACT FROM AUTHOR]