A firewall is a network security device that filters incoming and outgoing traffic.
A firewall controls incoming and outgoing traffic by allowing or blocking data packets according to predefined rules. It protects a network against intrusions and threats by filtering communications between an internal network and external sources, such as the Internet.
A firewall can be hardware or software. A hardware firewall is a dedicated physical device that filters network traffic.
Examples:
- Cisco Firepower
- Fortinet FortiGate
- Palo Alto Networks PA-7000 Series
- SonicWall Network Security Firewalls
Advantages :
- Protects the entire network
- High performance
- Does not consume server resources
A software firewall is an application installed on a computer or server.
Advantages :
- More flexible and configurable
- Less costly for small structures
- Can be installed on any appliance