The Connection Oriented Transport Service (COTS) is a connection-oriented transport service in a data packet network in which data transmission
takes place via an existing connection. Data transmission can only take place after a communication route has been established between the communication partners. The route between the communication partners can be permanently established, but it can also be virtual
or temporary, and can be taken down again after data transmission. In contrast to the connection-oriented
transport services are the connectionless transport services(
CLTS), which do not have an explicit route but take an individual route through the network.