Note that in response to the request from the base station 1, the network node may transmit the information it has previously collected to the base station 1 without executing the processes of S603 to S605, by periodically collecting the information on the communication delay from the base station that is under its control. In this way, the communication frequency for collecting information can be reduced. Furthermore, even if a request is not received, the network node may also provide information on the communication delay to the base station under its control. In this case, the base station may extract, of the information on the communication delay received from the network node in advance, information on the communication delay for the other base station specified in the candidate base station information from the terminal device, and transmit the information to the terminal device. According to this configuration, fewer requests are transmitted to the network node in correspondence with the candidate base station information from the multiple terminal devices, and thus, the communication frequency and the communication amount in the network can be reduced.

Note that, as described above, the communication quality at each base station may be obtained by collecting information indicating the communication quality actually measured when the communication opposing device connected to and communicated with a base station in the past. According to this configuration, the terminal device can determine in advance the communication quality predicted to be obtained in the actual communication environment when connected to a base station that is a candidate for the handover destination. An example of a flow of communication quality collecting processes in such an actual environment is illustrated in FIG. 7.