A network is a system that can communicate with each other in autonomous, physical, and logical ways, usually created by computers, and share resources.
What is a Computer Network?
Computer networks can differ in terms of their physical structures, physical connection structures, and types in the data flow. They consist of two or more computers that share certain resources that contain hardware or software.
A network, which is more than a few connected computers, consists of several or more people who seek, provide, and exchange information through communication systems.
Since their emergence, computer networks similar to a spider web have continued to evolve as required by verbal or visual communication needs between individuals and the enterprise.
The first networking structures used the ARCNET (Attached Resource Computer Network) protocol developed by Datapoint Corporation in the 1980s.
At the time, networks used coaxial cables and had 2.5 Mbps data transfer, which was considered high speed. Because of the slow data transmission, users were sharing information via the parallel or serial port.
The first computer network emerged 35 years ago during the cold war, and scientists at UCLA in the US use a cable to connect two computers to stream data from one machine to another.
This development was the beginning of the ARPANET, which is now recognized as the forerunner of what is now known as the Internet.
Arpanet was created during the cold war, and its main purpose was to centralize the military information of the United States so that, in the event of an attack, its military information was accessible from anywhere in the country.
As the use of Arpanet increased, remote nodes were created at other US institutions such as the Stanford Research Institute and the University of Utah. And then, when using the first communication system, the TCP/IP protocol that worked as standard in networks was created.
At that time, TCP/IP was thought of as an Internet network because it could share information between very different structures. In 1983, Paul Mockapetris and Jon Postel developed the DNS (Domain Name System) protocol.
After these improvements, with the rapid growth of computer networks in the early 1990s, Tim Berners-Lee created the World Wide Web. Tim Berners, the invention of WWW, did not patent his invention to remove obstacles to the development of the Internet. Because of these achievements, the British royal family has awarded him a knight, and Time magazine named him one of the 20 most influential thinkers of the 20th century.
In the 1940s, computers were massive electromechanical devices that were prone to failure, while in 1947 the invention of the semiconductor transistor enabled the creation of smaller and more robust computers.
In the 1950s, mainframe computers running on punch card programs began to be used regularly by large corporations. At the end of this decade, an integrated circuit was created that combines many and today millions of transistors into a small semiconductor.
In the 1960s, integrated circuits began to be widely used. In the late 1960s and 1970s smaller computers called minicomputers were invented. However, these minicomputers were still very slow by modern standards.
In 1977, Apple Computer Company introduced the microcomputer, also known as a personal computer. In 1981 IBM introduced its first personal computer.
Micro miniaturization of integrated circuits has led to the widespread use of personal computers in homes and businesses. In the 1980s, users with standalone computers began using modems to connect to other computers and share files.
These communications were called point-to-point or dial-up communications and expanded with the use of computers acting as the central point of contact in the dial-up connection.
These computers were called bulletin boards, and users were connected to bulletin boards where they sent messages as well as upload and download files. The disadvantage of this system was that there was little direct communication and it was only between people who knew the bulletin board. It was also that a modem was needed for every connection to the bulletin board computer.
When five people were connected at the same time, five modems connected to five different phone lines were required. Therefore, as the number of users increased, the system could not meet this requirement.
Starting from the 1960s and throughout the 1970s, 1980s, and 1990s, DoD (United States Department of Defense) developed the highly reliable WAN technology for military and scientific use.
This technology operated in a different way than the point-to-point communication used by bulletin boards and enabled several computers to communicate in different ways.
The networking determined how data would be transferred from one computer to another, and instead of communicating with a single computer at the same time, multiple computers could be accessed over the same connection. Following this development, DoD WAN technology became today’s Internet.
Data Transmission Media
The medium used to transmit information between computers determines the speed of the network, the effective distance between devices, and the topology of the network.
Two-wire copper cables or coaxial cables support transmission rates of several thousand bps over long distances and about 100 Mbps over short distances. Optical fibers allow very high speeds over long distances.
Regarding wireless connection, it is possible to transmit data at distances between 10 and 100 meters.
Computer environments have three components: application software, network software, and hardware software.
Application software includes programs that communicate with users on the Internet and allow the sharing of information and resources.
It includes the protocols required for computers to communicate with each other. These protocols work by sending and receiving data blocks called packets.
It consists of hardware components that unite computers in a central environment.
The most important component is the adapter hardware, which carries the signals from computers, provides access to the hardware that connects devices, and receives packets from its software and transmits it to other computers.
Networking provides communication between groups of computers and associated devices, allowing users to transfer their information electronically.
In these structures, some computers are called workstations and they communicate with each other via a cable or telephone line connected to the servers.
Servers are like workstations, but they are computers with management functions and only allow monitoring and control of access to the environment and shared resources.
Shared structures are structures in which a large number of users participate, share all their transmission needs, and provide centralized transfers.
Non-public structures are systems that do not consist of security, speed, or any other type, and only connect two or more points. This structure can be used in point-to-point or multi-point environments.
This type is managed by private individuals, companies, or organizations and is structures that only allow administrators to access certain services.
This type is owned by government agencies and is open structures focused on a user requested through the relevant contract.
Local Area Networks (LAN)
A LAN is an interconnection system for computer equipment based on high-speed lines and generally covering no more than one building. The main technologies used in a LAN are Ethernet, Token Ring, ARCNET, and FDDI.
A typical LAN is to have a LAN server computer where users install applications to run on their workstation. Users can use print jobs and other services through applications running on the server.
They can also share files with other users on the server, and access to these files is managed by a LAN administrator.
Metropolitan Area Networks (MAN)
A MAN is a method of interconnecting computers distributed over an area containing several buildings, by means of vehicles belonging to the same organization that owns the equipment. MAN is often used to interconnect LANs.
Wide Area Networks (WAN)
A WAN is an interconnection system of geographically dispersed computers that are on different continents. These normally consist of public data transfer environments.
Network topologies refer to the way in which cables connecting computers are placed. The purpose of topologies is to provide the most economical and efficient connection way to increase the reliability of the system, reduce waiting times in transmission, provide better control of the networking and provide an efficient increase in the number of computers.
Computer network topologies are:
In a bus topology, computers are connected to a single communication channel and all devices appear to be connected to a single cable.
In a ring topology, computers are linked together to form a ring and each is connected to the next, and the last one is formed by connecting the first. Devices on the network connection directly to the server and all communication are done through it.
In a star topology, nodes are connected in the form of a tree and topologically, this connection is similar to a series of interconnected star networks.
In a tree topology, a physical connection is established between all computers using point-to-point connections that will allow any computer to communicate with others in parallel when needed.
In a mesh topology, it is used in most of today’s local networks through hubs or switches arranged in stages to form a hierarchical environment.
Protocols are one or more systems of standards that determine the method of sending and receiving data between multiple computers or devices. The main reason for not having a single network protocol is that the same computer can communicate with different networks.
Every protocol configured in a system can be used for all existing physical or logical adapters in that system. If the devices and protocols are not configured correctly, networking resources can be accessed by unwanted people.
The TCP/IP protocol was developed in the late 1960s to allow computers to connect to different operating systems.
In order for a computer environment to be effective and efficient, it must provide a set of services below.
Access services include services that allow the user to connect from remote locations for authentication to determine the resources to use.
The file service allows downloading, deleting, or configuring user data from computers connected to the networking.
This service allows applications and data to be stored on the server, thus reducing the storage requirements of computers.
The printing service shares printers among multiple users and thus plays an important role in lowering the firm’s costs.
The e-mail service is the most common application used on the networking. This service provides convenience in online communication and reduces costs in information transmission.
The information service provides access to files based on content such as hypertext and presents information to be processed by applications on database servers.
Benefits of Building a Networking
A networking is an efficient structure for centralizing and distributing information stored within a corporate organization to users who request it.
As a result, by creating a networking, social interactions, teleconferences, video calls can be made, online purchases and capital movements can be monitored, and important data and e-mails can be transferred in real-time.