ABSTRACT

GENERAL DESCRIPTION OF WORK

Urgency. With an increasing number of mobile users there is rising up an emergency in the rapid establishment of communication between them, in data exchange, in fast access to information. Wi-Fi - the modern wireless technology of connecting computers to local network and connecting them to the Internet. Due to this technology, Internet goes mobile and gives the user freedom of movement not only in the rooms, but all over the world.

A weighty contribution to the scientific advances relating to the design and development of wireless networks, have made such scientists as Vic Hayes, Frank Hanzlik, Alexei Umnov, Thomas Little, Pat Calhoun, Stefan Savage.

Work relationship with academic programs, plans, themes.

Masterwork is performed in 2009 respectively the scientific direction of the "Digital computers" department of Donetsk National Technical University.

Research purpose – construction of wireless network with automatic IP-routing.

To achieve this purpose it is necessary to:

Research object – routing in IP-networks.

Research subject – routing algorithm in wireless networks.

Research methods: sets and graphs theory, programming languages - for implementation of wireless network model.

Scientific novelty of expected results:

The practical significance of the results:

The validity and reliability of the research confirms the correctness of the application of the theory of IP-networks and routing, application software implementation models, as well as the adequacy of the results.

The results of the master's work will be used in the educational process of DonNTU at the CI department of CST faculty.

MAIN WORK CONTENT

The introduction contains the ground of actuality of the scientific problem solvable, formulate purposes, objectives and research tasks, the totality of scientific findings made by the defense, information about their approbation.

The first chapter deals with issues relating to generally accepted methods of constructing multisegment networks based on wireless devices. It describes the advantages of wireless networks and discusses their limitations, leading to a reduction in the speed and reliability of data transmission. Showing specific examples of situations where the provision of clients with wireless inevitably leads to additional hardware cost that is often unacceptable.

In the second chapter a method of wireless network organization is offered, which consists in providing with of wireless devices the set of functions, before dispersed on different devices. I.e. structurally combine the functions of an access point, router and client in one device. An algorithm was developed, according to which such devices will provide the proper routing of packets between different network segments.

The algorithm of the network is as follows. The client, located in a certain range of the access point, turns to it with a request to connect to the Internet. And, if the access point is not connected to "ground" line, and, respectively, can not provide the necessary services for a client, it makes a similar request to all other wireless devices (access points, routers) within a radius of action. If the device received a request from the access points are connected to the Internet, they answer a consent to the grant of services. Choosing one of the providers is done on the analysis of the quality of communication: the power of the signal, level of work-load of retransmitting device.


Figure 1 - Illustration of developed routing algorithm
(figure is animated; loops count = 7; frames count = 9; size = 152.8Kb)

Thus, possibility of the use of access points in a role of wireless bridges for retransmitting of information from a segment, located far from Internet-node is provided, and also these access points will be able still to serve the clients of own subnet.

The third chapter focuses on the development of the simulator software. This software implement a routing algorithm, visualize a work of complex wireless network, allows to determine the area of effective application of the developed routing algorithm.

In the fourth chapter a method for estimating the effectiveness of the routing algorithm is offered. Above the model of wireless network experimental researches are conducted. Quantitative characteristics of routing algorithm are got.

Important remark. During author's abstract writing master work is still not completed. Final completion: December, 2009. Work's full-text and materials on theme can be get from author or his supervisor after mentioned date.

Literature

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