A communication terminal apparatus comprising: a collection control unit configured to collect communication of an application; an analysis unit configured to analyze the communication collected by the collection control unit by a statistical technique or machine learning to collect communication patterns of the application and to use identification information about the application, to classify, by fitting a change in a cumulative value of the communication pattern to a curve, the application whose communication pattern has not converged as an application that is not the communication control target, and classify the application whose communication pattern has converged as an application that is the communication control target and to identify a normal communication range of the application that is the communication control target, and configured to generate a first control condition based on the normal communication range of the application that is the communication control target, wherein the first control condition at least indicates a packet size and a number of targets of transmission and wherein communication that satisfies the first control condition is referred to as normal communication and communication that does not satisfy the first control condition is referred to as abnormal communication; and a coordination unit configured to transmit first shared information including identification information about the application and the first control condition to a second communication terminal apparatus that is different from the communication terminal apparatus; wherein the coordination unit is configured to receive second shared information including identification information about the application on the second communication terminal apparatus, information indicating whether the application is the communication control target, a second control condition corresponding to a normal communication of the application, the second shared information being set by the second communication terminal apparatus; and wherein the analysis unit is further configured to, when communication that does not satisfy the first control condition occurs, to perform re-analysis to set the first control condition by referring to the first shared information and the second shared information and to re-analyze the communication of the application generating such communication. a collection control unit configured to collect communication of an application; an analysis unit configured to analyze the communication collected by the collection control unit by a statistical technique or machine learning to collect communication patterns of the application and to use identification information about the application, to classify, by fitting a change in a cumulative value of the communication pattern to a curve, the application whose communication pattern has not converged as an application that is not the communication control target, and classify the application whose communication pattern has converged as an application that is the communication control target and to identify a normal communication range of the application that is the communication control target, and configured to generate a first control condition based on the normal communication range of the application that is the communication control target, wherein the first control condition at least indicates a packet size and a number of targets of transmission and wherein communication that satisfies the first control condition is referred to as normal communication and communication that does not satisfy the first control condition is referred to as abnormal communication; and a coordination unit configured to transmit first shared information including identification information about the application and the first control condition to a second communication terminal apparatus that is different from the communication terminal apparatus; wherein the coordination unit is configured to receive second shared information including identification information about the application on the second communication terminal apparatus, information indicating whether the application is the communication control target, a second control condition corresponding to a normal communication of the application, the second shared information being set by the second communication terminal apparatus; and wherein the analysis unit is further configured to, when communication that does not satisfy the first control condition occurs, to perform re-analysis to set the first control condition by referring to the first shared information and the second shared information and to re-analyze the communication of the application generating such communication.