In telecommunications, a n-entity is an active element in the n-th layer of the Open Systems Interconnection--Reference Model (OSI-RM) that (a) interacts directly with elements, i.e., entities, of the layer immediately above or below the n-th layer, (b) is defined by a unique set of rules, i.e., syntax, and information formats, including data and control formats, and (c) performs a defined set of functions.
The n refers to any one of the 7 layers of the OSI-RM.
In an existing layered open system, the n may refer to any given layer in the system.
This article incorporates public domain material from Federal Standard 1037C.
General Services Administration.