A firewall is a defensive technology designed to keep cybercriminals out. Firewalls can be hardware or software-based.

Businesses can use a network firewall to protect resources from outsiders and to control employees’ access to sensitive data. Organizations can implement the firewall themselves, or they can outsource the implementation. Small businesses often secure their computers with a personal firewall utility. A personal firewall is a utility application that identifies and defends a personal computer and its data from unauthorized attacks. Another typical purchase for small businesses is a hardware firewall, such as a router that has a built-in firewall.

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Secure Sockets Layer (SSL)