What Is a Firewall?
A firewall is a security function designed to prevent attacks from external communications. It serves as a barrier between a private internal network and the public internet, much like a fire-resistant wall in a building offers protection against fire.
There are two primary types of firewalls: packet filtering and gateway firewalls. Packet filtering analyzes and blocks dangerous information packets from external sources, while gateway firewalls filter information based on destination URLs or specific text content.
Given the diverse information confidentiality and volume handled by organizations like companies and schools, firewall settings and functionalities often vary to meet specific needs. For instance, some institutions may use firewalls to block access to social networking sites to mitigate the risk of information leakage.
How Firewalls Work
Firewalls operate by monitoring data packets, which are units of data transmitted over a network. They identify and block unauthorized or potentially harmful activities. There are two types of firewalls:
- Packet Filter Type: Filters data packets based on their headers, which contain information about the packet.
- Gateway Type: Filters content based on URLs or text within the communication’s destination.
Firewalls also regulate internal PCs’ communication with potentially hazardous external destinations, preventing both external attacks and unsafe internal communications.
Firewalls in the Enterprise
In corporate environments, firewalls are crucial for maintaining information security. Unlike personal computers, the information handled by companies and schools often includes sensitive data, necessitating robust security measures.
Firewalls in these settings not only provide basic filtering, but may also restrict access to websites that could potentially lead to information leaks. Information security teams typically manage these firewalls, updating software, monitoring connections, and deciding on blockages as needed.
Firewall Settings
While firewall settings are generally predetermined by the application developers and offer limited user customization, some adjustments are possible. Users can modify settings to allow connections through specific ports or to certain sites. However, free alteration of firewall settings in corporate environments is typically restricted to prevent accidental security breaches.
Risks of Disabling Firewalls
Disabling a firewall, even temporarily, exposes a network to external threats. It’s vital to re-enable the firewall promptly after such instances. Moreover, outdated firewalls can also compromise network security, highlighting the importance of regular updates and maintenance.