What Is a Firewall?
Firewall is a security device that regulates inbound and outbound network traffic between external public networks like the global Internet and internal private networks such as home Wi-Fi networks, businesses, or government agencies. It prevents cyber threats from breaching sensitive data and disrupting critical operations by observing and controlling network traffic based on pre-programmed rules. Firewalls can be deployed as dedicated hardware appliances, software firewall solutions, or virtual firewall systems. Major cybersecurity companies and technology providers manufacture and market firewall products to protect different types of network infrastructures.
The firewall’s access control functionality is based on packet filters that examine incoming and outgoing network connections, allowing or blocking certain types of traffic based on user and resource permissions. Packet filters examine a combination of identifiers including IP addresses, ports, and protocols. They use these to determine whether a packet should be discarded, dropped, or forwarded. Packet filtering is less sophisticated than stateful inspection, which monitors the status of established network connections and makes more informed decisions about incoming packets based on their relationship to previously approved communication sessions.
An advanced network firewall will offer robust logging and reporting capabilities to monitor possible suspicious activities, support compliance initiatives, and optimize the performance of the firewall. Look for a system that allows you to customize and create reporting templates, supports real-time monitoring dashboards, and can be integrated with external logging and analytics platforms. Robust logging and reporting capabilities are especially important for firewalls that are part of an overall cyber threat defense stack that includes anti-malware, antivirus, and intrusion prevention technologies.