Firewall – (1) A computer program or hardware device used to provide additional security on networks by blocking access from the public network to certain services in the private network. (2) It is an integrated collection of security measures designed to prevent unauthorized electronic access to a networked computer system. It is also a device or set of devices configured to permit, deny, encrypt, decrypt, or proxy all computer traffic between different security domains based upon a set of rules and other criteria.
Etymology Firewall is consisting of two words “fire” and “wall”.
Fire can be traced from the Old English word fyr a Germanic language which means “fire, torch”. In Old Czech language pyr means “hot ashes”. Moreover, wall is can be traced from the Old English word weall which means “rampart” (natural as well as man-made) and “defensive fortification around a city, side of a building, interior partition,” which apparently a borrowing from Classic Latin vallum which means “wall, rampart, row or line of stakes”.
However, the term firewall, as we used here, is a recently coined term for network security and technology. History and Background The term “firewall” originally meant a wall to confine a fire or potential fire within a building, c. f. firewall (construction). It was also used later on as a referral to similar structures, like metal sheet that separates the engine compartment of a vehicle or aircraft from the passenger compartment. Firewall technology emerged in the late 1980s when during that time Internet was a fairly new technology in terms of its global use and connectivity.
The forerunners to firewalls for network security were the routers used to separate networks from one another in the mid to late 1980s. Firewalls are important for the following reasons: it can block unauthorized users to access your network; it can protect the network from attacks using the e-mail system; it can prevent vandals from logging into the machines on your network; and it can serve as a tracer for those who attempted to use your network’s data.