Network Security


Network Security

Network security is the processes or steps put in place to prevent unauthorized or illegal access to a computer network.

A computer network is the interconnection of 2 or more computers for the purpose of information and resources sharing.

There are 2 major types of network, Wide Area Network (WAN) and Local Area Network (LAN).

Local Area Networks are networks within a small geographical space such as an office or a house while Wide Area Networks are networks over a large geographical area.

Such as different offices of a large corporation in different states of a country or international networks.

Network is key to secure a network organisation

Types of networks based on their organization scope include Intranets (a set of network which in most cases is the internal Local Area Network of an organization controlled by an administrative entity)

Extranet (is a network that can connect to specific external networks but controlled by a single administrative entity)

Internet work (connection of more than 1 computer with the same routers.

Internet (is the largest type of network available and it gives access to a lot of services especially the World Wide Web

It could also be used for instant messaging, video calls and many other services), and Dark net (a type of network that runs basically on the internet but accessible only by a special software.

network security

There are two major ways to connect to a network: through a wired technology and through a wireless connection.

Wired connections involves through the use of cables such as coaxial cable, ITU-T technology, twisted pair cable and optical fiber, while you could connect wirelessly through terrestrial microwaves, communication satellites, cellular and PCS systems, radio and spread spectrum technologies, free-space optical communications and hotspots.

Networking has been very useful as it has helped a lot of people to transfer information, files and data over large distances and also the advent of the Internet which is the largest type of network.

The computer network allows people to communicate through services such as email, video conferencing, video telephone calls, telephone and chat rooms.

A network also allows user to share resources such as printers and scanners.


There is however, restricted information on many networks which sometimes unauthorized users try to gain access to, hence, the need for network security.

Network security is put in place to deny unauthorized access to such information or computers.

While small networks in homes and offices might require only basic security, larger networks would require higher network security and powerful effective software and hardware to prevent hackers and spammer’s access to their network.

Network Attacks by malicious users or hackers can be divided into passive attacks (where data is being interrupted while traveling from one computer to another) and active attacks (where there is a direct attack on one of the on the network or one of the computers on the Network).


The types of attacks include wiretapping, cyber-attack, buffer overflow, SQL injection, port scanner, denial of service attack, spoofing, mind in the middle, idle scan, scurf attack, format string attack and heap overflow.

In order to avoid these attacks, effective network security is put in place to prevent unauthorized access of malicious users.

Networks in most cases authenticates user before they can have access to restricted information as a form of security.


The authentication could be in the form of entering a username and password, Automated Teller Machine (ATM) card, token, mobile phone retinal scan and/or fingerprint.

Most networks are also protected with firewalls that prevent illegal access from other network users.

Antivirus software is important network security software as it helps to protect against computer worms, Trojans, malware and spyware.


Encryption is another important network security technique as it codes the data being sent over computers so that even if an unauthorized user should have access to such data, he would not be able to decode it.


Network security is thus, very important when setting up network connections no matter how small so as to avoid unauthorized access to sensitive information or computer of other users.