Liberios Vokorokos

Network Security on the Intrusion Detection System Level

In the present security is an important factor of the network protection. Not only intrusion detection system but also intrusion prevention systems are created in order to the system failure due to a deliberate harm or a system intrusion is not occurred. The article deals with an analysis of the intrusion detection systems. The main goal is to point out an advantages and disadvantages of these systems and provide the overview of the possibilities which these systems offer. The article asset is the possibility to implement such a system to the network in its separate levels of the ISO/OSI layered model on the Department of Computers and Informatics of the Faculty of Electrotechnical Engineering and Informatics of the Technical University of Kosice. The main asset should be the network protection by using intrusion detection systems

Data preprocessing for efficient evaluation of network traffic parameters

This paper deals with recent results of a supporting mechanism for efficient evaluation of network traffic parameters. Most of the network monitoring tools store the measured data in a database for the later analysis. With the growth of the data in the database, processing of queries is becoming more and more time consuming. This fact results in an excessive response time of the database, which subsequently brings an adverse impact on the monitoring tool. While most of the monitoring tools make evaluations on the basis of outdated data from a database, the vast majority of them have to deal with this problem. In this contribution a new approach of efficient network traffic data evaluation through a database will be introduced, while the main attention will be dedicated to the implementation details.

Distributed intrusion detection system using self organizing map

The goal of the article of to present intrusion detections system and design a two layer architecture of distributed intrusion detection based on the neural network self-organizing map. First layer consists of detection sensors which provide basic processing of input data on behalf of statistical methods with a direct connection to countermeasure modules. Performance and accuracy of the modeling system is ensured by using central distributed processing, in which the detection of generalized description with self-organizing map is used, preventing the intrusion itself.

Preparing databases for network traffic monitoring

This paper deals with the solution of database related problems which can occur during network traffic monitoring. During data evaluation through a database excessive response time can be noticed. While the time necessary to obtain the data from the database has a significant effect on the result of the monitoring, it is important to keep its value as low as possible. Practically, the vast majority of the monitoring tools have to deal with the problems related to the databases excessive response time, so their solution is really justified. In this paper an alternative method of network monitoring, the BasicMeter tool will be introduced by which the exact problems and their solution will be illustrated.

The process control for P-single operators

The architecture described in this article belongs to a class of dynamic data flow architectures, in which the operand process control significantly affects the performance parameters as well as the system characteristics of the given architecture. The main component of the presented architecture is the multifunctional pipeline unit, which handles processing of data tokens representing the instructions of the program. This article describes the pipelined single operand data flow operators process control.

Performance optimization of applications based on non-relational databases

This paper is focused on performance optimization of applications based on non-relational databases. Firstly there will be explained differences between relational and non-relational databases and also compared the types of non-relational databases. Then the advantages and disadvantages between MongoDB and ElasticSearch (SQL) database systems will be described and compared. After both database systems were implemented on the web server, their speed is compared in order to determine which system is better to use in different conditions and tasks.

Priority of instructions execution and DFG mapping techniques of computer architecture with data driven computation model

The article introduces proposed computer architecture with data driven computation model based on principles of tile computing as the modern approach to multi-core design of microprocessors. Special attention is paid to the description of characteristics of architecture, which are priority of instructions execution with coloring of instruction priorities, data flow graph mapping technique and multi-mapping technique, which are proposed within this architecture. Architecture is developed at the Department of Computers and Informatics, Faculty of Electrical Engineering and Informatics, Technical University of Košice. The work is one of reached results within projects APVV-0008-10 and KEGA project No. 3/7110/09, being solved at the Department of Computers and Informatics, Faculty of Electrical Engineering and Informatics, Technical University of Košice.

Operand processing and P-single operators

The data flow model of execution offers attractive properties for parallel processing. First, it is asynchronous: Because the readiness of data dictates the instruction execution. Second, it is self-scheduling: The data flow graph representation of a program eliminates the need to explicitly manage parallel execution. The architecture described in this article belongs to a class of dynamic dataflow architectures, in which the operand process control significantly affects the performance parameters as well as the system characteristics of the given architecture.

Task scheduling in distributed system for photorealistic rendering

Today Computer graphics belongs to intensive developing areas of informatics. For realization calculations imaging of 3D objects in computer graphics are needs high efficient computers, which enable user to work with graphic information. One option to achieve needed power for photorealistic imaging is to use distributed systems. By planning system is considered static assigning and sharing of scene based on areas. This project will make imaging more effective from time aspect in distributed systems, because nod utilization will be balanced.

The obfuscation efficiency measuring schemes

Obfuscation is primarily used as a tool for protecting the written code against reverse engineering. But there also exist other schemas for the obfuscation process, which primarily focus on hiding the true purpose of the written code by transforming its blocks, which causes the inability of comparison the obfuscated code sequence to code stored in database by static or hybrid analysis. When trying to overcome this type of analysis weakness, man should be well educated in the obfuscation schemas.