FIG. 8 is a drawing illustrating an example of a functional structure of a base station apparatus 10 according to an embodiment of the present invention. As illustrated in FIG. 8, the base station apparatus 10 includes a transmission unit 110, a reception unit 120, a configuration unit (setting unit) 130, and a control unit 140. The functional structure illustrated in FIG. 8 is merely an example. Functional divisions and names of functional units may be anything as long as operations can be performed according to an embodiment of the present invention.

The transmission unit 110 has a function for generating a signal to be transmitted to the user apparatus 20 and for transmitting the signal wirelessly. Further, the transmission unit 110 transmits an inter-network-node message to another network node. The reception unit 120 has a function for receiving various signals transmitted from the user apparatus 20 and for obtaining, for example, upper layer information from the received signals. Further, the transmission unit 110 has a function for transmitting to the user apparatus 20 NR-PSS, NR-SSS, NR-PBCH, DL/UL control signals, etc. Further, the reception unit 120 receives an inter-network-node message from another network node.