transport system (TS)
The transport system is a term from the OSI terminology. In the OSI reference model, the OSI architecture distinguishes between the lower four layers - these are the transport-oriented layers - and the upper three layers, the application-oriented layers.
The transport-oriented layers form the transport system, which consists of the transmission medium and data and communication networks with their accesses and switching equipment - the bridges, routers, switches, packet and line switches - that are built on top of the transmission media. The transport-oriented layers include the physical layer, data linklayer, network layer and transport layer.
In the OSI concept, the transport-oriented layers are implemented by access methods and transport protocols. In contrast, the application-oriented layers, which realize the user system, support with the presentation, the correct syntax of the data and the application protocols.