Classification by Scale
Computer networks may be classified according to the scale or extent of reach of the network, for example as a Personal area network (PAN), Local area network (LAN), Campus area network (CAN), Metropolitan area network (MAN), or Wide area network (WAN).
Personal area network
A personal area network (PAN) is a computer network used for communication among computer devices (including telephones and personal digital assistants) close to one person.
The devices may or may not belong to the person in question.
The reach of a PAN is typically a few meters.
PANs can be used for communication among the personal devices themselves (intrapersonal communication), or for connecting to a higher level network and the Internet (an uplink).
Local area network
A local area network (LAN) is a computer network covering a small geographic area, like a home, office, or group of buildings.
Current LANs are most likely to be based on switched IEEE 802.3 Ethernet technology, running at 10, 100 or 1,000 Mbit/s, or on IEEE 802.11 Wi-Fi technology.
Each node or computer in the LAN has its own computing power but it can also access other devices on the LAN subject to the permissions it has been allowed.
These could include data, processing power, and the ability to communicate or chat with other users in the network.
Campus area network
A campus area network (CAN) is a computer network made up of an interconnection of local area networks (LANs) within a limited geographical area.
It can be considered one form of a metropolitan area network, specific to an academic setting.
Metropolitan area network
Metropolitan Area Networks, or MANs, are large computer networks usually spanning a city.
They typically use wireless infrastructure or optical fiber connections to link their sites.
A MAN is optimized for a larger geographical area than is a LAN, ranging from several blocks of buildings to entire cities.
As with local networks, MANs can also depend on communications channels of moderate-to-high data rates.
A MAN might be owned and operated by a single organization, but it usually will be used by many individuals and organizations.
MANs might also be owned and operated as public utilities. They will often provide means for internetworking of local networks.
Wide area network
Wide Area Network (WAN) is a computer network that covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries).
). Or, less formally, a network that uses routers and public communications links.
Contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), or metropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively.
The largest and most well-known example of a WAN is the Internet.