Wyniki wyszukiwania - BazTech

1

The impact of selected parameters on the performance of routing protocols in wireless sensor networks

Piechowiak M., Zwierzykowski P., Kotlarz P., Żmudziński P.

Image Processing & Communications

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2017

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Vol. 22, no. 1

57--62

EN

The aim of the article was to compare the effectiveness of the selected routing protocols for wireless sensor networks taking In to account a number of speciﬁc parameters as network troughput, packet error rate and message buffer capacity for different network topologies. The simulation research was conducted in open source OMNeT++ environment. In order to achieve the assumed requirements, four different-sized network topologies were established and AODV and DYMO routing protocols were adapted.

2

The influence on network topology on the efficiency of multicast heuristic algorithms

Piechowiak M., Żmudziński P.

Image Processing & Communications

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2006

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Vol. 11, no 1

41-51

EN

The article investigates representative heuristic algorithms finding the cheapest spanning trees between a source node and the group of destination nodes (multicast connections). Reliable comparison and analysis of the efficiency of algorithms require the usage of network structures reflecting real Internet topology. This article also presents method for generation that topologies. The key part of the article includes the efficiency analysis and the influence of the parameters of a given structure (network model generated by BRITE tool) upon the efficiency of the algorithms under scrutiny.

3

The attack on the RSA algorithm with the application of Euler's function

Kotlarz P., Żmudziński P., Dunajewski I.

Image Processing & Communications

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2006

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Vol. 11, no 1

25-31

EN

The security of present-day asymmetric encryption algorithms is based on certain limitations of modern mathematics. A wide range of applications of asymmetric cryptography in commonly and widely used network protocols poses a question as to what degree such solutions, in a situation where the security of the used algorithm is not given once and for all, are really safe? In the vast majority of instances, a discussion on security involves considerations on the problem of factorization. The attack, derived almost from the definition, is an attack that involves trying many different options to intercept the private key, indispensable for decryption of the encrypted message, on the basis of the intercepted public key. The present work discusses possibilities and the feasibility of an attack on the RSA algorithm using two given methods, factorization and the method that implements Euler's function. The paper presents an analysis of potential costs (time and computational) for both presented methods. The article also includes a discussion on strong and weak keys for the RSA encryption. The quality of the keys is discussed taking into account the aforementioned two algorithms carrying out an attack against the encryption algorithm.

4

Comparative evaluation of distributed Bandwidth Broker

Żmudziński P., Piechowiak M.

Image Processing & Communications

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2006

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Vol. 11, no 1

59-69

EN

The Differentiated Services (DS) framework is one of the basic architectures that have been proposed for provision in the Internet. One of the most significant advantages of DS is ability to distinguish management plane of the network to provide the customer Quality of Service. A DS architecture proposed by IETF alone is not sufficient to address the end-to-end guaranties in a network layer but it does show great potential for scalability. To fulfill negotiated QoS services Bandwidth Broker - an additional management entity, has to be implemented. The main tasks of the Broker are: limiting the traffic volume carried through the managed domain and services nego-tiation on behalf of domain with customers and adjacent brokers. The authors concentrated on the concept of distributed Broker as a more scalable and efficient solution. The different bandwidth allocation scenarios are presented and compared with regard to signaling overhead, admission control delay and control complexity. The quota-based admission control algorithm has been briefly described and discussed. The new style of reservation has been proposed to decrease the amount of signaling traffic between core and edge routers. The example of its functioning has been given at the end of the presented paper.