The correct answer is firewall.A firewall is a system that prevents unauthorized access to a private network.It is a type of cybersecurity tool that is used to filter traffic on a network.A firewall will create a barrier between a secured internal network and an unsafe external network.Additional Information Firewalls are of two types namelyNetwork firewalls: Use to protect whole computer networks from attacks.Host-based firewalls.: Installed on servers or host computers to protect them from attacks.A firewall can be hardware, software, or both.