Communication system, mobile station, and communication method

A communication system comprising:

• a mobile station connectable to an IP access network conforming to Internet protocol via any one of a first radio access network supporting a particular service conforming to the Internet protocol and a second radio access network not supporting the particular service conforming to the Internet protocol;
• and
• a switch capable of communicating with the particular service conforming to the Internet protocol, wherein
• the switch includes a connection rejection notification unit configured to transmit a connection rejection notification to the mobile station if the switch receives a request for reconnection to the IP access network from the mobile station via the second radio access network, the connection rejection notification indicating that the mobile station is not connectable to an APN used in the particular service conforming to the Internet protocol, and
• the mobile station includes a reconnection suspension unit configured to, in a case where the mobile station receives the connection rejection notification from the switch after transitioning from the first radio access network to the second radio access network, suspend transmission of the request for reconnection to the IP access network only if the mobile station is camping in the second radio access network through which the connection rejection notification has been received.