What Does Node Mean?
A node is a point of intersection/connection within a data communication network. In an environment where all devices are accessible through the network, these devices are all considered nodes. The individual definition of each node depends on the type of network it refers to.
For example, within the physical network of a smart home domotics system, each home appliance capable of transmitting or receiving information over the network constitutes a node. However, a passive distribution point such as a patch panel would not be considered a node.
Nodes create, receive and communicate information and store it or relay it to other nodes. For example, a scanner in a computer network creates images and sends them to a computer, while a router organizes data received from the internet and distributes it to the individual devices within the network.
The concept of nodes works on several levels, but the big-picture view defines nodes as the major centers through which internet traffic is typically routed. This usage is somewhat confusing, as these same internet nodes are also referred to as internet hubs.
Techopedia Explains Node
The idea of nodes was popularized with the adoption of packet-switching theory and the concept of distributed networks. In this context, nodes were gateways that could receive, store and send information along different routes through a distributed network. Each node was given an equal standing within the network, meaning that the loss of any one node would not significantly hurt the network. (See also: Network Topology)
When applied to an office or personal network, however, a node is simply one of the devices that performs a particular function. As such, the loss of that node usually means the loss of function, such as the inability to use a printer. The connections between the nodes of the network can be made with cables (wired network) or using other, wireless technologies such as communication satellites, terrestrial microwave, Bluetooth or Wi-Fi.
Here are some examples of network nodes:
Computer network nodes
In a computer network such as a local area network LAN or wide area network WAN, nodes may be personal computers as well as other pieces of data terminal equipment (DTE) and data communication equipment (DCE). This can include equipment such as modems, routers, servers and workstations. Each of these nodes is identified by a MAC address, and its function is lost if it goes offline. (See also: EndPoint)
Internet network nodes
In internet or intranet networks, each host computer constitutes an internet node identified by an IP address. Other datalink layer devices that do not have an IP host address (such as bridges or switches) but have a MAC address are still considered to be physical network nodes or LAN nodes, but not internet nodes. (See also: Layer 2, Datalink Layer)
Distributed system nodes
In peer-to-peer or other types of distributed networks, nodes are comprised of the servers, clients and/or peers. Peers themselves can act both as servers and clients, while nodes that route data for other devices within the network are defined as “supernodes.”
Telephone network nodes
In traditional telecommunication networks such as telephone networks, every individual telephone or smartphone is a node, along with other databases and switching points such as a Gateway GPRS Support Node (GGSN) and a Home Location Register.
Cable TV system nodes
In cable television systems (CATV), nodes have a broader meaning, usually associated with fiber-optic nodes. Each fiber optic node represents the number of homes or businesses that could be served via cables originating from a given fiber optic receiver.