What is a Firewall?
Firewall is a network security solution that monitors the incoming and outgoing data packets from your computer or server and permits or denies access based on a set of rules and criteria. It creates a barrier between your private network and the internet to prevent hackers and malicious traffic from penetrating your system and damaging it.
Firewalls are available as hardware or software. They can be installed on a single computer to protect that particular machine, or on a network to protect multiple computers. Most operating systems include a built-in firewall feature that you should enable for added protection. Firewall software is also sold at local computer stores and software vendors.
Incoming and outgoing data packets are identified by their source and destination addresses and their port numbers, which indicate the applications that created them. A firewall analyzes a given data packet and compares it against a list of threat signatures to decide whether it should be allowed through.
Firewalls can filter based on different sets of criteria including IP address, domain names and other parameters. They can also monitor and detect anomalies in a network, which are often signs of hacker activity.
The effectiveness of firewalls largely depends on their correct configuration. Deviations or oversights in this process leave openings for cyberattackers to exploit, which can lead to unforeseen vulnerabilities. Regularly reviewing and adjusting the settings of your firewall will help to keep it up-to-date against changing threats.