Chernobay Yuriy
Faculty computer sciences and technologies
Department: The computer engineering
Theme of master's work: Research-and-development methods of collection and treatment of information is in a global network
Scientific leader: Teplinskiy Sergey
Research-and-development methods of collection and treatment of information is in a global network
Introduction
In our time in the conditions of globalization of business, requiring the fall-off of expenses on implementation of production functions, mobility of personnel, possibilities of access to the required information and work with it in any point of the world, it is impossible to imagine life without the systems of collection and treatments of information, the main indexes of which is an increase of levels of safety and availability of informative resources (informative arrays, bases of knowledges and programmatic modules) and effective management by them.
Actuality
Using of Internet of technologies for creation of the systems of collection and treatment of information and construction of the informative systems of the different setting in the near time will become dominant in outer informative space on next reasons. These technologies:
- Allow to organize with sufficient simplicity for the user of the system of necessary information retrieval;
- Produce minimum requirements, both from a technical side and from the side of software to the workplace of client;
- Support the distributed systems of storage of information and plural methods of its storage;
- Support work with the practically unlimited volume of the versatile information;
- Give technologically simple method of administration of the informative systems from one workplace;
- Support the remote methods of editing and addition to information.[7].
In connection with these tendencies creation IS on-line of payment of public utilities is an appropriate process. With the increase of popularity of ecashs by creation of great number the Internet of shops and auctions people all anymore want to pay and get services and commodities, staying in a house over the internet. Therefore creation IS on-line of payment communal will allow not only to economize time of people which do not need it will be to conduct by hours upright in turns but also automatize and accelerate the process of payment. Also man at any time and in any place can obtain information on the state the debt and to the tariffs on public utilities in real time, the state of which can be changed the representatives of services.
Methods of collection and treatment of information are in a global network
For realization of collection and treatment of i6nformacii the distributed informative systems are more frequent than all used in a global network. Informative system - an aggregate of the technical, programmatic and organizational providing the basic task of which is satisfaction of concrete informative necessities within the framework of concrete subject domain.[4]
Distributed informative systems on architecture it is possible to divide into two basic types:
1. File-server IS (IS with architecture "file-server");
File-server applications are appendixes, similar on the structure with local applications and using a network resource for storage of the program and information. Functions of server: storages of data and program. Functions of client: processing of data takes place exceptionally on client-side. The amount of clients is limited in tens.
Pluses: low cost of development; high-rate of development; low cost of update and change SOFTWARE.
Minuses: low productivity (depends on a network, server, client performance); bad possibility of connecting of new clients; unreliable system; narrow-mindedness of language; unflexibility of environment of development.[5]
2. Client-server IS (IS with architecture "client-server").
Usually under a term a "client-server" is understood architecture of the Multiplayer systems, which foresees the presence of client and server programmatic component. The client modules are used on the remote workplaces of users, and the centralized server programs provide service" of "customers, that reception of remote queries of users, their treatment and return by him results of this treatment.[8]
Advantages:
- Does possible, in most cases, to distribute the functions of the computer system between a few independent computers in a network.
- All information is kept on a server, which, as a rule, is protected much better than most clients.
- To use the resources of one server often clients can with different vehicle platforms, by the operating systems etc.
Failings:
- The uncapacity of server can do disabled all computer network;
- Support of work of this system, requires a separate specialist - system administrator;
- High cost of equipment.[6]
In same queue client-server architecture is divided into a few types:
- Two-tier architecture is a "client-server";
- Three-level architecture is a "client-server";
- Layered architecture or n-level architecture.
Two-tier architecture is a "client-server".
In case with two-tier architecture "client-server" a database is placed on a network server, however deprived the program of client is possibility of randomaccess to DB. Access to DB is regulated the special program – server of DB.
Co-operation of server and client DB realized by sql-queries which forms and sends a server client. A server, accepting a query, executes him and returns a result a client. In client application mainly carried out interpretation got from the server of information, realization of user interface, and also realization of part business-governed.[9]
But two-tier architecture is not deprived failings, such as:
- Worsening of the productivity to the have linear dependence amount of users;
- Regardless of what type of client is used, greater part of processing of data must be in a database, it means that it fully depends on possibilities foreseen in a database a producer.
- Two-tier architecture so depends on concrete realization of database, that transfer of existent applications for different DMBS, becomes a serious problem.[10]
Three-level architecture is a "client-server".
The second method of co-operation is three-level architecture "client-server". In this model a process, executed on a client, answers, for an interface with an user. Applying for implementation of services to the application entity. An application entity is realized as a group of processes, executing the applied functions, and named the server of appendix. All operations above the informative resources of databases are executed component`s of access to the resources. Thus, unlike previous architecture, an exchange between a client and server is carried out by means of the specially developed set of commands (API), but not SQL to the queries. Meeting of these commands is determined a developer, that allows him to limit the set of possible actions with information accessible to the client. Three-level architecture client server presented on a picture 2.[9]
Introduction of additional level allows to overcome some limitations of two-tier architecture, described broadly speaking higher. As well as with a two-tier model, levels can be disposed or on different computers, or on one computer in the test mode.[10]
The layered architecture is a “client-server”.
Layered architecture a client-server is a variety of architecture client-server, in which the function of processing of data is taken away on one or a few separate servers. It allows to divide the functions of storage, treatment and presentation of the servers and clients given for more effective use of possibilities.[6]
Three-level architecture is the special case multilevel, but if to examine them separately that can be selected a few advantages of the layered architecture are before three-level, such as:
- Scaleableness. Loading is distributed on a few web-servers which co-operate with a database or with the server of next level.
- Protected. The use of a few physical levels is promoted by protected of the informative system from network attacks, and also function all levels of server can execute defence, distributing loading.
- Stability. At outcommissioning one of intermediate levels can distribute his function between itself other levels of identical functionality. Though the productivity will get lost in such situation,
but the system will not be put out of action as in the case of the three-level system.
The layered architectures usually consist of four levels (picture 3), where in a network a server is responsible for treatment connection between a client a browser and server of appendixes.[10]
Picture. 3. The layered architecture is a "client-server".[10]
Aims and tasks of master's degree work
Considering the existent methods of collection and treatment of information, the followings tasks are put in master's degree work:
- To analyse and compare the different methods of organization of n-level architecture "client-server";
- To study the existent methods of partition of load on server, and to develop the own method of the even distributing of connecting to the servers;
- To develop the system on-line of payment of public utilities on the basis of the layered architecture using a "client-server" the got results of research;
- To develop own protocol of exchange information between a client and server, using for a transmission a format this XML (text format, intended for storage of the structured data);
- On the base of the developed system to analyse scaleableness and productivity of the system depending on the increase of amount intermediate servers.
Practical value and scientific novelty
The designed system is a software product which allows to carry out on-line payment of public utilities. The use of the layered architecture of "client-server" application allows simultaneously real-time to serve plenty of clients simultaneous.
The scientific novelty of work consists of that will be created system of collection and processing of data on the basis of the layered architecture "client-server". The basic feature of the system consists of that will be created the up-diffused server side which depending on loading on a server can be extended at physical level. And also the increase of the productivity will be investigational at expansion.
Practical results
The methods of collection and treatment of information were considered in a global network, failings and advantages are analysed each of methods. The program was also developed on-line of payment of public utilities on the base of three-level architecture "client-server".
In the developed system the client program, written on actionscript 3, is loaded on the computer of user as ordinary flesh is a file from a server. Started, this program is connected to the server, to written on C#, using a database MS SQL. The queries of client are passed in the format of XML, which on the side of server is decrypted and on the basis of findings Sql is formed query to the base. Thus a server before forming of query checks up all comings commands. Meeting of exchange instructions between a server and client is very limited and allows to execute the only certain set of actions with a database. However much such approach for creation of narrowly specialized DMBS justifies small functionality large protected of database. The format of XML is very comfortable for communication of data, but he is opened and clear even for an ordinary man. So for defence of these users at a transmission on a network the standard methods of encipherement of transferrable information are used. Realized a program-client will be disposed on a computer with the set http server, and will be accessible to any user, to having an access in the Internet. Loaded on the computer of user and started it will be as an ordinary flesh-roller through a browser, and will not require the additional setting. For work of program-client on the computer of user must will be any browser and Flash Player is set versions not below 10.0. Program a server for greater safety can be disposed on any other server machine without set http and ftp servers and protected firewall-ohm. Such localization of parts of the programs considerably promotes safety of server with databases and eliminates possibility of remote access to the files of the program and database.[9]
Also expansion of the system is in the future planned to fourlevel architecture, realization of algorithm of the even distributing of clients between servers, and also to analyse scaleableness and productivity of the system depending on the increase of amount of intermediate servers.
Conclusion
This master's degree work is devoted the actual theme of creation of the informative system, using the layered architecture of client-server. Swift development is instrumental in permanent development and improvement of such systems the Internet of technologies.
The methods of collection and treatment of information analysed in-process allow to create the stable and flexible in a down-scaling system.
It should be noted that in Ukraine there are not companies of the similar informative systems specialized on creation. Usually such systems are as necessary developed the groups of programmers, not having an experience of development in this sphere of activity, that results in the inefficient use of resources, uneffective work of the system and permanent revision and correction of the created system.
Literature
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- Вийера Р. Програмирование баз данных Microsoft SQL Server 2005 для профессионалов / Р. Вийера // 2008. 256с.
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