To lessen the vulnerability of the computer to the network there are many products available. Organizations have an extensive choice of technologies, ranging from anti-virus software packages to dedicated network security hardware, such as firewalls and intrusion detection systems, to provide protection for all areas of the network.
It is important to point out that no single solution protects a system from a variety of threats. A network security system usually consists of many components. Ideally, all components work together, and if one fails, others still stand, improving the security. These components can be hardware and/or software. The software must be constantly updated and managed to protect you from emerging threats.
Organizations today use combinations of firewalls, IDS, encryption, and authentication mechanisms to create “intranets” that are connected to the Internet but protected from it at the same time. Intranet is a private computer network that uses internet protocols. Intranets differ from "Extranets" in that the former are generally restricted to employees of the organization while extranets can generally be accessed by customers, suppliers, or other approved parties.