| 摘要 |
<p>A network communication system comprises a network (7), the system of an authentication server (5), and terminals (1). The system of the authentication server comprises a plurality of servers (501, 502) for receiving authentication requests from the terminals (1) to execute predetermined processes. Each of the terminals (1) comprises: a connection destination list storing unit (43) that has stored information of a predetermined preferential connection order of the servers; an abnormality determining unit (204) that determines whether any traffic abnormality has occurred in one of the servers during requesting an authentication from the server; and a preferential order setting unit (203) that, when it is determined that any traffic abnormality has occurred, switches the connection to the next server in accordance with the connection order. Even while the server is being DOS/DDOS attacked, the authentication process in the server can be executed as much as possible.</p> |
