Rabu, 31 Desember 2014

NETWORKING BASICS

NETWORKING BASICS CONCEPT

Computer network-a set of stand-alone computers for joint solution of information, computing, and other tasks. Two computers are related if they can exchange information. The requirement of autonomy here is used to exclude from consideration of the decentralized system (one computer can control the other force). System with one control device and are not multiple managed network. In a distributed system, there are numerous independent PV rsonal′nye computers is transparent (invisible to other users). Users of such a system, setting the team, unaware of the existence of several processes execute the given command. In computer networking, the user must explicitly register on one machine and explicitly specify the remote setting. The simplest type of network is a peer-to-peer, which link personal computers of end users and enables you to share printers, files, drives. More advanced network in addition to end-user computers (workstations) include dedicated computer servers. Server is a computer that performs specific functions in the network services to other computers on the network.

USE of COMPUTER NETWORKS 

The use of computer networks:

  1.  sale of air and railway tickets; 
  2.  access to information in computer databases and databanks; 
  3. exchange of information between the slave. a teacher and a servant. places pupils. The use of computer networks:

networking basics concept

  1. In organizations:
  • resource sharing cat provide access to programs that are given to any user regardless of NAT. the location of the resource and the user;
  • ensure high reliability through the use of alternative sources of information;
  • opportunity cost savings;
  • scalability;
  • the possibility of rapid communication between remote employees.
  1. individuals:
  • Remote access to information;
  • Communication;
  • interactive games, video, TV;
  • e-business.
  Networks Architecture «Client Server Types» Server types:
  • print server — attach the printer to the network via a specialized node processing print jobs;
  • DB server is a shared database;
  • file server is the data store;
  • communication server-manages access to remote resources, provides a channel of communication with global figures. network;
  • application server-run specialty computing jobs (handling graphics);
  • Web Server — provides access to Web pages.
Very popular today and extremely promising technology of information processing in the network name.«client-server». In the function «client» includes:
  • providing a user interface for certain production duties and powers;
  • query to the server;
  • analysis of server responses to and bring them to the user.
The primary function of the server is to perform a specific action at the request of the client (for example, the solution to a difficult mathematical problem, search data in the database, your connection with another client, etc.); the server itself does not have any interactions with the customer. If the server to which the client has failed to solve the problem of a lack of resources, then ideally they find another, more powerful server and transfers the task of it, becoming, in turn, by the client, but not informing the primary client unnecessarily.