Let’s start with Unit II Computer Networks, in this article, we will cover the Evolution of Networking Class 12 including data communication terminologies and the transmission media.
We have almost completed Unit I – Computational Thinking and Programming. If you missed any part of that you can refer to the below-given link and check it out!
Before starting this unit please refer this article for Networking, which we have already written on our blog.
Evolution of Networking Class 12
As you already know that Jio and the 4G network made a huge impact on our lives. Nowadays almost everyone is having a smartphone and has a 4G network connection with an active internet connection.
Every day you are using emails, uploading status on Facebook, Whatsapp and Instagram, watching videos on YouTube, searching on Google etc. These all are somehow connected to the network.
The network basically provides a connection with different devices and resources for sharing purposes. Let us know about the evolution of the network.
Observe the following picture to understand the evolution of networking.
ARPANET – 1960
In the 1960s, the U.S. Department Of Defence had started a project named Advanced Research Projects Agency Network (ARPANET) to provide an interconnection between academic and research institutions for research purposes. They have started communication and the first message was communicated between the University of California, Los Angeles (UCLA) and Stanford Research Institute (SRI). Later on, other organizations had also joined ARPANET gradually and formed small networks.
Email – 1971
In 1971, Roy Romlinson develops a networking message popularly known as E-mail. With this, the symbol @ is used the first time with the network. Click here to read more about E-mail.
Internet – 1974
In 1974, the commercial use of ARPANET started in the name of TelNet. Later on, the word internet was coined.
TCP/IP – 1982
By using the ARPANET project, now it is almost spread over countries with TelNet. In 1982 they have started using TCP/IP protocol in ARPANET. This protocol was developed by Robert Kahn and Vinton Cerf.
Domain Name System – 1983
In 1983, the Domain Name System was started. It was created by Paul Mockapetris in November 1983 to use some simple names rather than using the traditional addresses used in the ARPANET.
NSFNET – 1986
NSFNET program was launched by National Science Foundation in 1986 to bring connectivity to more people. It was popularly used to promote advanced research and education networking in the United States.
WWW – 1990
In 1990, Tim Berners Lee worked with European Organization for Nuclear research developed a program to make information readily available to users with different URLs and create relationships between websites, thus it gives birth to World Wide Web.
WiFi – 1997
In 1997, the first version of WiFi was introduced. Later on, so many changes and evolution took place and modern hi-speed internet came into the existence.
In the next section of Evolution of Networking Class 12, we will discuss a few data communication terminologies given in the curriculum document.
Data Communication Terminologies
There are a few important terminologies you need to understand for data communication. These terminologies are as follows:
- Node/Host/Workstation: A computer that is attached to a network is known as node or host or workstation. Sometimes it is considered as a client as well.
- Server: A server plays an important role in the network. The server is the leader of the pack. It serves all the services as the requests of the client.
- Network Hardware: A device is used to established a network between various devices or connected to the network. There three main devices required to connect a computer with a network.
- NIC or NIU: It stands for Network Interface Card or Network Interface Unit. Every computer is having a built-in NIC. You can also install external NIC into the computers.
- Connecting Device: There are certain connecting devices available to connect different devices. These are the hub, switch, router, repeater etc. We will discuss them later.
- The communication Channel: It is the way of connecting network hardware with each other. A communication channel is the type of cable used to connect the various devices into the network. We will discuss all types of cables later.
- Bandwidth: Bandwidth refers to the range of frequencies use into network data transmission. This bandwidth is available in Hz, KHz, MHz etc.
- Data Transfer Rate: The data transfer rate refers to the amount of data transmitted per second from one device to another. It is measured in bps, Kbps, Mbps, Gbps, Tbps, etc.
- Internet: Thousands of computers connected together globally is known as the internet. It is also considered as Network of Networks.
- Switching Technique: This term is associated with a large network. In a large network, there are multiple paths from sender to receiver. The switching technique will decide the best route for the network and connect system for making one-to-one communication. There are three types of Switching techniques:
- Circuit Switching: In this technique, two network nodes establish a dedicated communication channel (circuit) through the network.
- Packet Switching: In the packet switching technique, data is divided into small packets, not in a single unit.
- Message Switching: Data choose a specific route from source to destination one hope at a time.