A node is a device that is connected as part of a computer network. Every node must have a MAC address or Data Link Control address if it is at least an OSI model layer 2 device. Nodes can be computers, personal digital assistants (PDAs), cell phones, or various other network appliances, such as routers, switches, and hubs. Nodes that actively route data for the other networked devices as well as themselves are called supernodes. In broad general terms, a node is a specific location in a telecommunication network. In Cable TV systems (CATV), this term has assumed a broader context and is generally associated with a fibre Optic Node. A fibre optic node is those homes or businesses within a specific geographic area that are served from a common fibre optic receiver. A fibre optic node is generally described in terms of the number of Homes Passed that are served by that specific fibre node. Network node (NN): A grouping of one or more network elements (at one or more sites) which provides network related functions, and is administered as a single entity. A single site may contain more than one network node. For the purpose of this glossary, a network node is considered synonymous with a network element, and is usually at a single site. This restriction simplifies the definition of the network node interface (NNI) and INI, which would not apply between network elements. In networks, a processing location. A node can be a computer or some other device, such as a printer. Every node has a unique network address, sometimes called a Data Link Control (DLC) address or Media Access Control (MAC) address.