Computer Network Basics

ARPANET:

ARPANET is the shortest form of Advanced Research Projects Agency Network. The history of ARPANET is interesting because it’s the start of the INTERNET. ARPANET is built up for research purposes, it’s funded by the Pentagon. It mainly starts with telephone lines.

The reason for the ARPANET is that military commanders want a computer communication system without a central core. Finally, the defense department successfully made a call in January 1969 Bolt, Beranek, and Newman (BBN) of Cambridge, Massachusetts, won the $1 million contract.

Network:

The network is the meaning of connection. After the invention of the stream engine, the network idea was established. In a computer system, network mean the connection of minimum two computer system.

What is a Computer Network

A computer network is a set of computers connected together for the purpose of sharing resources. This connection can be made by wire or wireless. Common example: Internet, exchange files, or allow electronic communications.

Goals Of Computer Network:

• Sharing Resource

Sharing Resources from one computer to another computer over. Like when we share files or communicate with each other.

• Performance

Performance is one of the major issues in networking because we always want speedy data transmission and communication.

• Reliability

Without reliability, computer networks can not be a secure or efficient communication system. A reliable network system is ensured to use an alternative for data transmission if any hardware issue or connectivity issue.

• Scalability

For increasing performance and reliability using more resources is scalability.

• Security

Security is also another main goal of computer network systems. 

Application of Computer Network:

• Business Applications

For business purposes, we must communicate with each other. Like B2B, B2C, or marketing between customers. Without networking it’s not easier or effective.

• Communication Medium

The modern telecommunication system is totally dependent on a communication medium, computer networks provide us with a wire/wireless medium. Different type cables, microwave communication also.

• E-Commerce

Electronic commerce is another invention and application of computer network systems. It helps us receive products from home at a cheap price and less work.

• Home Applications

Home applications like Micro Oven, Washing machine, Air Conditioning System, Remote control base Television and other electronic components are the example application area of computer networks.

• Mobile Users

Today’s mobile is not limited to call to each other, now using mobile network data communication like internet use, roaming is also possible. This is possible by computer networks.

Component of Computer Network:

There are mainly three types of components in the Computer Network.

1. Hardware Equipment
2. Software
3. Cables and Connectors

Hardware Components:

• NIC: NIC’s full form is Network Interface Card. It’s the most important hardware device for connecting with the Internet. Without NIC it is not possible to connect over with a Network, then it’s not possible to share resources or communicate anything.

• Server: The server is the HOST of the computer network. It’s sharing resources, data, and services to build up the network.

• Client: Clients are the users who access the resources, services, and data.

• Peers: Peers stand for Peer to Peer. It’s actually the device that connects the users.

• Transmission: For data to be sent and received we must need a transmission system and transmission media. Transmission media can be wire or wireless systems.

• Medium: Medium is the media between devices, it can be a cable, also it can be wireless.

• Router: Router is used for connecting between more than one devices. It’s a central point of all devices that are connected within the network.

• Bridge: Bridge is a hardware device, it can create a signal, aggregate it for multiple device communication. Its work is the same as a repeater.

• Hub: Hub is a hardware device, which allows creating networks between multiple devices through a cable, like an ethernet. Hub can broadcast data in every port which is connected with the device.

• Switches: Multiple devices can connect with a switch through their data cable. The switch can connect different devices to network devices.

• Gateway: Gateway is the gate between two networks. It may be a router, firewall, server, or other devices that enables traffic to flow in and out of the network.

• Repeaters: A repeater is a device that works as a signal amplifier. It receives a signal and amplifies it, then it again transmits it.

Softwares:

• Network Operating System: Network Operating System is Computer Operating System (OS) that actually is used for specific large or small networking systems. Like workstations, personal computers, Local area networks, etc.
• Protocol Switches(TCP/IP, OSI): Protocol is the rules of communication between two or more devices. Actually, it allows devices to communicate with each other, regardless of any differences in their internal processes, structure, or design.

There are several types of network protocol. Like TCP/IP, OSI model.

Transmission Control Protocol/Internet Protocol (TCP/IP) is a communications architecture used for networking computers and communicating across the Internet.

Otherhand, The OSI Model (Open Systems Interconnection Model) is a conceptual framework used to describe the functions of a networking system. 

Cables and Connectors:

• Twisted pair cable: Twisted pair cable, from the name it’s clear that it’s a wire with twisted wire. Twisted wire is use due to reduce the noise of the cable. Because normal cable generating huge noise with their signal. There are two types of twisted cables.

1. Unshielded Twisted Pair (UTP)

2. Shielded Twisted Pair (STP)

There are also categories Twisted Pair Cable. These cables name Category 1 to Category 7.

• Coaxial cable: Coaxial cables, commonly called coax, are copper cables with metal shielding designed to provide immunity against noise and greater bandwidth. Coax can transmit signals over larger distances at a higher speed as compared to twisted pair cables.

Fiber-optic cable: A fiber optic cable is a network cable that contains strands of glass fibers inside an insulated casing. They’re designed for long-distance, high-performance data networking, and telecommunications. Compared to wired cables, fiber optic cables provide higher bandwidth and transmit data over longer distances. Fiber optic cables support much of the world’s internet, cable television, and telephone systems.