Family of communications protocols and related abstract model (the "OSI reference model") developed by the ISO, most of which are incompatible with the Internet protocols.
The only internationally-accepted framework of standards for communication between different vendors. The OSI model organizes the communications process into seven different categories and places these categories in layered sequence based on their relation to the user: Layer 1- Physical Layer Layer 2- The Data Link Layer Layer 3- The Network Layer Layer 4- The Transport Layer Layer 5- The Session Layer Layer 6- The Presentation Layer Layer 7- The Application Layer
A multi-layer ISO data communications standard. Level Seven of this standard is industry-specific, and HL7 is responsible for specifying the level seven OSI standards for the health industry.
An ISO standard for worldwide communications defining a framework for implementing protocols in seven layers. Control is passed from one layer to the next, starting at the application layer in one station, proceeding to the bottom layer, over the channel to the next station and back up the hierarchy.