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How a firewall protects a network

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A firewall works as a network gateway and provides a protective wall over a network. Access through a firewall requires an authorization to then access the network.

The initial process for most firewalls involves installing a software to a user computer or over a network which initiates an access control policy on that network. Some firewalls are primarily for prevention of the flow of traffic, while some are primarily for easing the flow of traffic. Firewalls are of great importance in our present digital world, due to the surge of cyber-security concerns.

What can a firewall do?

A firewall can protect a network from unauthorized interactive access from the outside world. A network is guarded from strangers and unauthorized users.

A firewall can protect a network from external traffic, but can let authorized users have access with unhindered communication. In hardware terms, a firewall can protect the network against network-borne attacks when unplugged.

A firewall can protect users from an attacker who tries to connect a new application to the device while in use on the internet. It queries the user’s consent on this particular scenario. It also protects a user from an attacker trying to connect to an application that has not been captured on the filter rule stored on the firewall.

What firewalls can’t do

Firewalls are unable to protect a network when an authorized user or system tends to connect to an external user or system right from inside the system to outside. When this kind of connection is compromised, a firewall is unable to protect that system.

What a firewall protects a user from

Default setting

Some user systems come with certain pr-installed applications which can be accessed remotely. These applications could be seen as factory set applications. The remote access possibility of these applications creates room for intrusion of malicious codes into the application, which could cause harm on the user side. A firewall can be installed for applications to go through packet filtering each time data packets arrive remotely into the user systems.

Cyber attacks

Cyber-security attacks like denial of service (DOS) are very popular in current times. Most strangers can make a network server inaccessible by flooding the server with multiple access requests. This would reduce the server performance and could cause a breakdown. But when a firewall is installed, such attacks could be detected and hindered so as to stop a breakdown of the server.

Malicious spam

Firewalls can prevent users from falling prey to spam links, mail, and messages. The spam messages create an open door for hackers to steal important information from users. Firewalls sieve this spam mail and blocks them so that users will not fall prey to them.

Viruses

Viruses could be very dangerous to a user, as they tend to compromise the user data and storage. Most times, the viruses keep increasing until the user is locked out of the system. Firewalls protect against viruses, and using anti-virus alongside firewalls can protect a computer totally.

Macros

Macros exist, like scripts, which help applications make complicated processes simple. A hacker can possibly inject their own macro to run in their own preference, so as to gain control of user applications. This can be observed and stopped by a firewall if put in place to defend the system.

RELATED TAGS

firewall
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