1.5. OSI and the ISO

The Open Standards Interconnect (OSI) series of models are an attempt by the International Standards Organisation (ISO) to standardise the way that computer systems communicate with each other. Although there are several OSI models, the most widely used one is the OSI reference model. This seven layer model is intended to ensure interoperability between different protocols and methods of communication. The layers of the OSI reference model are: physical, data link, network, transport, session, presentation, and application [Tanenbaum, 1988].

This work also makes reference to another, less commonly used, OSI model — the OSI network management model. This model describes the tasks associated with managing modern computer networks, and provides a way to define relationships between various tasks. The network management model is described in Section 2.1.