This European Telecommunication Standard (ETS) specifies the network specific aspects of the frame relay service when it is offered on a network to provide the frame relay data transmission service. This ETS is applicable for all networks providing the frame relay data transmission service. This service is offered on user-network interfaces where the physical layer is unstructured@ i.e. at any time@ there exists at most a single physical connection on the user-network interface. This ETS should be complemented with ETS 300 399-1 [1]@ for the common part of the frame relay service.