General English


  • noun a hardware or software security system between a server or intranet and the public Internet that allows information to pass out to the Internet but checks any incoming data before passing it on to the private server


  • A system which is utilized to help protect a network against threats originating through other networks, such as unauthorized access. A firewall, for example, enables an organization with an intranet to allow its members access to the Internet, while preventing outsiders from accessing its own private resources. A firewall may also control which outside resources are available to what users. A firewall may be implemented through the use of hardware and/or software, and all communications entering or leaving the internal network of the organization are examined to determine if they may proceed. application gateways, packet filters, and proxy servers are among the available techniques which help afford such protection. A firewall may also help protect a network against internal threats, such as snooping. Also called Internet firewall.

Information & Library Science

  • noun a piece of computer software intended to prevent unauthorised access to system software or data