A computer network is a system in which multiple computers are connected to each other to share information and resources.
Characteristics of a Computer Network
- Share resources from one computer to another.
- Create files and store them in one computer, access those files from the other computer(s) connected over the network.
- Connect a printer, scanner, or a fax machine to one computer within the network and let other computers of the network use the machines available over the network.
NODA
A node is any physical device within a network of other tools that’s able to send, receive, or forward information. A personal computer is the most common node. It’s called the computer node or internet node.
Modems, switches, hubs, bridges, servers, and printers are also nodes, as are other devices that connect over Wi-Fi or Ethernet. For example, a network connecting three computers and one printer, along with two more wireless devices, has six total nodes.
Nodes within a computer network must have some form of identification, like an IP address or MAC address, for other network devices to recognize it. A node without this information, or one that’s offline, no longer functions as a node.
In telecommunications networks, a node is either a redistribution point or a communication endpoint. The definition of a node depends on the network and protocol layer referred to. A physical network node is an electronic device that is attached to a network, and is capable of creating, receiving, or transmitting information over a communications channel. A passive distribution point such as a distribution frame or patch panel is consequently not a node.
Network nodes are the physical pieces that make up a network. They usually include any device that both receives and then communicates information. But they might receive and store the data, relay the information elsewhere, or create and send data instead.
For example, a computer node might back up files online or send an email, but it can also stream videos and download other files. A network printer can receive print requests from other devices on the network, while a scanner can send images back to the computer. A router determines which data goes to which devices that request file downloads within a system, but it can also send requests out to the public internet.
Client Server LAN
On a client/server network, every computer has a distinct role: that of either a client or a server. A server is designed to share its resources among the client computers on the network. Typically, servers are located in secured areas, such as locked closets or data centers (server rooms), because they hold an organization’s most valuable data and do not have to be accessed by operators on a continuous basis. The rest of the computers on the network function as clients.
The components of a client/server LAN.
Wide Area Network (WAN)
A wide area network (WAN) is a telecommunications network that extends over a large geographical area for the primary purpose of computer networking. Wide area networks are often established with leased telecommunication circuits.
Business, as well as education and government entities use wide area networks to relay data to staff, students, clients, buyers and suppliers from various locations across the world. In essence, this mode of telecommunication allows a business to effectively carry out its daily function regardless of location. The Internet may be considered a WAN.
Similar types of networks are 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, respectively.