NET.work Computer

Network Computer (often abbreviated NC) is a trademark of Oracle Corporation that was used, from approximately 1996 to 2000, to market a range of diskless desktop computer devices. The devices were designed and manufactured by an alliance, which included Sun Microsystems, IBM, and others. The devices were designed with minimum specifications, based on the Network Computer Reference Profile. The brand was also employed as a marketing term to try to popularize this design of computer within enterprise and among consumers.
The term, today, is also used somewhat interchangeably to describe a diskless desktop computer or a thin client.
The NC brand was mainly intended to denote and forecast a range of desktop computers from various suppliers that, by virtue of their diskless design and use of inexpensive components and software, were cheaper and easier to manage than standard fat client desktops. However, due to the commoditization of standard desktop components, and due to the increasing availability and popularity of various software options for using full desktops as diskless nodes, thin clients, and hybrid clients, the Network Computer brand never achieved the popularity hoped for by Oracle and was eventually mothballed
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local area network
A local area network (LAN) is a network that connects computers and devices in a limited geographical area such as home, school, computer laboratory, office building, or closely positioned group of buildings. Each computer or device on the network is a node. Current wired LANs are most likely to be based on Ethernet technology, although new standards like ITU-T G.hn also provide a way to create a wired LAN using existing home wires (coaxial cables, phone lines and power lines).

Campus network
A campus network is a computer network made up of an interconnection of local area networks (LAN's) within a limited geographical area. The networking equipments (switches, routers) and transmission media (optical fiber, copper plant, Cat5 cabling etc.) are almost entirely owned (by the campus tenant / owner: an enterprise, university, government etc.).
In the case of a university campus-based campus network, the network is likely to link a variety of campus buildings including; academic departments, the university library and student residence halls.

 Metropolitan area network

A Metropolitan area network is a large computer network that usually spans a city or a large campus.

Sample EPN made of Frame relay WAN connections and dialup remote access.

Sample VPN used to interconnect 3 offices and remote users

Enterprise private network

An enterprise private network is a network build by an enterprise to interconnect various company sites, e.g., production sites, head offices, remote offices, shops, in order to share computer resources.

 Virtual private network

A virtual private network (VPN) is a computer network in which some of the links between nodes are carried by open connections or virtual circuits in some larger network (e.g., the Internet) instead of by physical wires. The data link layer protocols of the virtual network are said to be tunneled through the larger network when this is the case. One common application is secure communications through the public Internet, but a VPN need not have explicit security features, such as authentication or content encryption. VPNs, for example, can be used to separate the traffic of different user communities over an underlying network with strong security features.
VPN may have best-effort performance, or may have a defined service level agreement (SLA) between the VPN customer and the VPN service provider. Generally, a VPN has a topology more complex than point-to-point.