This tutorial explains the basic and fundamental concepts of the computer networking. Learn the essential networking topics in detail with examples.
Computer networking is one of the most complex subjects. Describing all of its topics requires an encyclopedia. Learning and understanding all these topics at the primary stage are neither required nor recommended. It is just like learning the vocabulary from the dictionary. Unless you know what you need to know, you would not learn what you should learn.
I have already explained the definition, purpose and benefits of the computer networking in the following article.
In this tutorial, I will discuss two essential topics that you should learn at the elementary level. Understanding these topics will set the foundation for the rest of your studies.
Essential components of the computer network
When learning computer networking, this should be your first topic. A computer is built from the four essential components; End devices, Media, Protocols and Networking devices. Let’s understand each of these components.
An end device is the device that sends or receives the data or service in the network. An end device might be a PC, Laptop, Smartphone or any other device that is capable of the sending and receiving data the data and connected with the network. To build a network, at least two end devices are required.
Broadly end devices are categorized in two types; server end device and client end device. Server end device is the device which provides data or service. Client end device is the device which receives the offered data or service from the server end device.
The media provides connectivity between the end devices. Unless end devices are connected through the any kind of media, they cannot exchange the data or service. Mainly there are two types of media; Wireless media and wired media.
In wireless media, radio signals are used to transfer the data between end devices, whereas in wired media, the data is transferred through cables.
Both media types are further classified into several subtypes. Subtypes are categorized based on the various factors such as length, data transfer speed, used metal, frequency band, etc. Subtypes are defined as the media standards. Two common media standards are the Ethernet and the IEEE802.11 or Wi-Fi standards.
The Ethernet defines the standards for the wired media. The IEEE802.11 or Wi-Fi defines the standards for the wireless media.
Protocols enable communication between two or more end devices. A protocol is a set of predefined rules that specifies standards for a particular stage or all stages of the communication.
Following are the some common functions performed by the protocols.
- Initializing and terminating the communication process
- Performing encryption and compression before sending the data
- Packing data in such a format that it can travel in the network
- Providing logical addressing
- Performing error correction
- Performing authentication
Two popular networking models; OSI Reference model and TCP/IP model describe the functionalities of the most common protocols. Both models divide the entire communication process in logical layers. Further, they explain how the protocols work in each layer to enable the communication process.
A networking device works between the end devices. It controls and forwards the flow of data. Based on the functionalities, a networking device can be categorized in three types; forwarding device, connecting device and the securing device.
A forwarding device forwards the data. This device usually has multiple ports which are used to connect more than two end devices in a single network. Hub, bridge and Ethernet switch provide this functionality.
A connecting device connects two or more different types of media and protocols. If two end devices are located in the different logical networks or connected through the different types of media, they need a connecting device to exchange the data. Router and Multilayer switch provide this functionality.
A securing device secures the data from unauthorized access. When data packet arrives to it, based on pre-defined rules it performs security checks and takes the forwarding decision. Common devices which provide this functionality are the Firewall and NAT.
Classification of the computer network
Once you learned the essential components of the network, this should be your next topic. Computer networks are mainly categorized based on the geographical location, access types and relationship between end devices.
Based on the geographical location
Based on the geographical coverage, the network is classified into three types; LAN, MAN and WAN. Network that is geographically spread over a small, medium and large area is known as the LAN, MAN and WAN network respectively.
Based on the access type
On the basis of allowing users to access network resources, the network is classified into three types; Intranet, Extranet and Internet. An Intranet is a private network. In this network, external users are not allowed to access the network resources. An Extranet is also a private network. But in this network, after proper authorization, external users are allowed to access a small portion of the network. The Internet is the public network. Any user can connect with this network.
Based on the relationship between the end devices
Based on how the end devices access each other, the network is categorized in two types; peer to peer network and clients/server network. In peer to peer network, all end devices have equal rights. In clients/server network, server decides which client will have what rights.
Resources for further study
To learn the foundation topics introduced above, you can use the following tutorials.
This tutorial explains the seven layers of OSI Reference model.
This tutorial explains five layers of TCP/IP model (Application, Transport, Internet or Network, Data Link and Physical) and their functionality in detail.
This tutorial explains the different types of computer network and their characteristics in easy language.
This tutorial explains the functions of the most common and the essential networking devices in detail with examples.
That’s all for this tutorial. If you like this tutorial, please don’t forget to share it through your favorite social network.
Prerequisites for 200-301
200-301 is a single exam, consisting of about 120 questions. It covers a wide range of topics, such as routing and switching, security, wireless networking, and even some programming concepts. As with other Cisco certifications, you can take it at any of the Pearson VUE certification centers.
The recommended training program that can be taken at a Cisco academy is called Implementing and Administering Cisco Solutions (CCNA). The successful completion of a training course will get you a training badge.
Full Version 200-301 Dumps