What Is a Firewall?
Firewall is a term that’s used to describe a variety of devices – hardware or software – meant to protect your information by placing a barrier between your network and the Internet. These firewalls assess and manage incoming and outgoing network traffic to keep unsolicited data from entering or leaving the network and they help prevent malware from reaching your devices and users. Firewalls can be implemented as a stand-alone security measure or alongside other protective measures like virtual private networks and network address translations. Many devices come with built-in firewall protection, but it’s important to double-check the settings and consider adding extra layers of security, if needed.
A firewall creates a border between the network it guards and an external network, based on predetermined security rules. It tries to distinguish benign and malicious traffic and packets based on the set of rules and abides by them.
While a firewall does a good job of protecting the system from known threats, it’s important to ensure that it also keeps up with emerging ones by regularly performing a security audit. It is also recommended to check whether unauthorized changes have been made to the firewall configuration, as they may damage the security of the entire network.
Firewalls are often combined with other security measures, such as advanced authentication and packet filtering to provide more comprehensive protection. For instance, a next-generation firewall (NGFW) combines the traditional capabilities of packet filtering and stateful inspection with application awareness and an intrusion prevention system (IPS). Unlike standard packet filters that only look at the header of a package, NGFWs can inspect a packet’s payload and source to detect more sophisticated security threats.