Equipment used for information transfer. The information can be in the form of digital data for data communications or analog signals for traditional wireline voice communication
* Core network or equipment: A core network is a central network into which other networks feed. Traditionally, the core network has been the circuit-oriented telephone system. More recently, alternative optical networks bypass the traditional core and implement packet-oriented technologies. Significant to core networks is "the edge," where networks and users exist. The edge may perform intelligent functions that are not performed inside the core network
* Edge equipment or devices: In general, edge devices provide access to faster, more efficient backbone and core networks. The trend is to make the edge smart and the core "dumb and fast." Edge devices may translate between one type of network protocol and another