OSI network model is a networking framework that has seven layers that describes the encapsulation and communication of devices in a network. The seven OSI model layers are, application, presentation, session, transport, network, data-link and physical layer.
Each layer in this model describes the protocol datagram unit PDU and identifies several standard and proprietary protocols that can be used in a layer.
A network administrator of engineer can decide to use a protocol based on his choice and the brand of network device used.
