Functionality of a Firewall

Firewall is a hardware or software-based security system that controls network traffic entering or leaving a network (Rouse, 2014). Firewalls have important functionalities whether implemented for network security or access control. To begin with, firewall safeguards data being sent to different network locations by encrypting the data automatically. This feature allows organizations to use internet as a private WAN (Wide Area Network) by implementing VPN (Virtual Private Network) (White, 2016). Secondly, firewalls monitor and record all events that occur between networks; for example, penetration attempts and amounts of data exchanged. Firewall may also be utilized in access-controlled systems and networks. Additionally, firewall protects internal network from external attacks by blocking attackers and alerting network security personnel. It is also important to note that firewall blocks malicious applications and malware from entering the network.

Example of a Firewall

Windows Firewall is a very popular example of software firewall. It protects the computer from external malicious attacks like worms, Trojans and viruses. Windows firewall protects a specific windows machine from intrusion and attacks. In a small network, the router acts as a hardware firewall that can be configured from the setup screen. The router can be configured to block certain addresses and network traffic. In some cases, people configure routers to block certain social media and pornographic sites.


Rouse, M. (2014). Firewall. Retrieved July 31, 2017 from

White, C. M. (2016). Data communications & computer networks: a business users approach. 8th ed. Boston, MA: Cengage Learning.

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