A communication terminal comprising: a content storage means for storing a content containing first time information indicating a specified time unit of information representing a time; a terminal information storage means for storing terminal information containing second time information indicating a time unit shorter than the specified time unit and assigned to the communication terminal; a time determination means for determining whether it has reached a time consisting of the first time information and the second time information; and a content update means for performing a content update process when the time determination means determines that it has reached a time consisting of the first time information and the second time information; characterized in that the second time information is adapted to be assigned at the time of factory shipment of the communication terminal or generated randomly at the first start of the communication terminal; the communication terminal further comprising: a communication state determination means for determining whether the communication terminal is in a communication-enabled state; a random number generation means for generating random numbers; and a waiting time decision means for deciding a waiting time within a specified length of time based on the random numbers generated by the random number generation means, wherein, in a case where the communication state determination means determines that the communication terminal is in a communication-disabled state when the time determination means determines that it has reached a time consisting of the first time information and the second time information, the content update means is adapted to perform the content update process upon lapse of the waiting time decided by the waiting time decision means after the communication terminal returns to the communication-enabled state. a content storage means for storing a content containing first time information indicating a specified time unit of information representing a time; a terminal information storage means for storing terminal information containing second time information indicating a time unit shorter than the specified time unit and assigned to the communication terminal; a time determination means for determining whether it has reached a time consisting of the first time information and the second time information; and a content update means for performing a content update process when the time determination means determines that it has reached a time consisting of the first time information and the second time information; characterized in that the second time information is adapted to be assigned at the time of factory shipment of the communication terminal or generated randomly at the first start of the communication terminal; the communication terminal further comprising: a communication state determination means for determining whether the communication terminal is in a communication-enabled state; a random number generation means for generating random numbers; and a waiting time decision means for deciding a waiting time within a specified length of time based on the random numbers generated by the random number generation means, wherein, in a case where the communication state determination means determines that the communication terminal is in a communication-disabled state when the time determination means determines that it has reached a time consisting of the first time information and the second time information, the content update means is adapted to perform the content update process upon lapse of the waiting time decided by the waiting time decision means after the communication terminal returns to the communication-enabled state. a communication state determination means for determining whether the communication terminal is in a communication-enabled state; a random number generation means for generating random numbers; and a waiting time decision means for deciding a waiting time within a specified length of time based on the random numbers generated by the random number generation means, wherein, in a case where the communication state determination means determines that the communication terminal is in a communication-disabled state when the time determination means determines that it has reached a time consisting of the first time information and the second time information, the content update means is adapted to perform the content update process upon lapse of the waiting time decided by the waiting time decision means after the communication terminal returns to the communication-enabled state.