What is a Firewall?
Firewall is a computer network security system that regulates internet traffic in, out, and within private networks by selectively blocking or allowing data packets. Firewalls act as gated borders that manage the travel of authorized and prohibited web activity within a private network and slow the spread of threats from inside or outside the agency.
A firewall examines each piece of information that moves through the system to see if it meets your service access policy. Each piece of data contains header information that designates the sender, destination, and application that it’s meant for. The firewall checks the header to determine whether the information is a threat or not and then opens or closes the gateway accordingly.
The most basic type of firewall is a packet filtering firewall. This was the first type of firewall and it examines each packet, or bundle of bits, of data that is sent across the network to make sure it complies with the service access policy. Packet-filtering firewalls are still in use today and are a vital component of modern network security systems.
A more advanced type of firewall is a stateful inspection firewall. This type of firewall can analyze a network’s traffic over time and can make dynamic decisions based on the data patterns it observes. This type of firewall can also provide more advanced security features like bandwidth prioritization and network segmentation. However, it requires a high level of technical skill to properly implement and maintain and can be expensive for smaller agencies.