Eldsveggakerfi

Eldsveggakerfi, commonly translated as firewall, is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Firewalls act as a barrier between a trusted internal network and untrusted external networks, such as the internet. They examine data packets and decide whether to allow them through or block them based on a set of rules, effectively preventing unauthorized access, malicious attacks, and data breaches.

There are several types of firewalls, including hardware, software, and cloud-based solutions. Hardware firewalls are physical devices that sit between a network and the internet, offering robust protection for an entire network. Software firewalls are applications installed on individual computers, providing security for that specific device. Cloud-based firewalls, often referred to as Firewall-as-a-Service (FaaS), are hosted in the cloud and offer scalable, flexible security for organizations of all sizes.

Firewalls employ various inspection methods, such as packet filtering, stateful inspection, and application-layer gateway. Packet filtering examines the header of each data packet, checking source and destination IP addresses, ports, and protocols. Stateful inspection goes a step further by tracking the state of active network connections, allowing for more intelligent decisions. Application-layer gateways analyze the content of data packets at the application level, providing deeper inspection and security for specific applications. Firewalls are a fundamental component of network security, essential for protecting sensitive data and maintaining the integrity of computer systems.