Internet, Intranets, and Extranets
firewall
a security system consisting of a combination of hardware and software that limits the exposure of a computer or computer network to attack from crackers most commonly used type of security device in an organization's perimeter network
internet
like a big spiderweb that connects computers, devices and smaller networks all around the world
intranet
private computer network within an organization access is limited by permissions set by that organization enables a way for ppl to share resources privately and securely some connected to internet; some are not some have different access levels
extranets
private intranets extended to authorized users outside the organization
perimeter network
small physical or virtual sub-network that is set up between a company's private local area network (LAN) & untrusted networks such as the internet often a physical structure that supports the logical extranet concept that was previously covered allows users outside of a company LAN to access specific services located on that perimeter network