Meaning – The term layer, refers to a group of services that is complete from a conceptual point of view, that is one out of a set of hierarchically arranged groups, and that extends across all systems that conform to the network architecture.
In the Open Systems Interconnection reference model, one of seven conceptually complete, hierarchically arranged groups of
services, functions, and protocols, that extend across all open systems.
In SNA, a grouping of related functions that are logically separate from the functions in other groups. Implementation of the functions in one layer can be changed without affecting functions in other layers.
Example of usage – “The designer was used to using layers to create the artwork and graphics for the clients. This way, if the client wants changes to be made on certain elements, he could simply change that particular layer.”