Patent ID: 8065258

Claim:
A computer-implemented method of determining validity of a command line, comprising the steps of: maintaining a log database, said log database including log information associated with command lines, said log information including at least one of network address information included in the command line, input time point information with respect to the input time point of the command line, and the request content information; receiving a command line from a terminal of a user; and determining validity of said received command line based, at least in part, upon log information recorded in said log database, wherein the step of determining the validity of the command line based, at least in part, upon the log information recorded in the log database comprises: computing first number of the command for a first period by using the log information recorded in the log database for the first period for each of the request content information, respectively, in which the command line received from the terminal with the same network address is determined to be received from one terminal, said log information including at least said blocked network address information and request content information; computing the second number of the command line including the request content information from the command line received from the terminal with the network address for a second period by using the log information recorded in the log database for the second period; and determining the validity of the command line by using the first number for said each terminal and for said each of the request content information and the second number.