Patent ID: 7554972

Claim:
A wireless communication terminal including a function of performing data communication with a server connected to a network, comprising: a wireless communication unit which performs wireless communication; a communication controller which connects to the network using the wireless communication unit, establishes a point to point protocol (PPP) connection with the server, selects a predetermined port number from among a plurality of port numbers allocated for data communication with the server as a communication port number, and establishes a transmission control protocol (TCP) connection using this communication port number to perform data communication with the server; and a storage unit which stores the communication port number; wherein: the communication controller determines whether the TCP connection is in a SYN_SENT state in which the communication controller waits an acknowledgement in reply to a synchronization (SYN) packet when the communication controller receives information indicating that communication connection is impossible from the server using the communication port number during establishment of the PPP connection; if the communication controller determines that the TCP connection is in the SYN_SENT state, the communication controller maintains the PPP connection and selects a port number which is different from the communication port number stored in the storage unit as a new communication port number, and performs the process again to establish the TCP connection using the new communication port number; and if the communication controller determines that the TCP connection is not in the SYN_SENT state, the communication controller releases the TCP connection and the PPP connection.