A transmission method comprising: a process for transmitting an authorization file in a communication system, wherein said process for transmitting includes transmitting through a secure link to a terminal unit a security descriptive file as said authorization file from an administering server unit storing said security descriptive file the security descriptive file containing first identification information and authorization information, the first identification information showing a storage location of an application descriptive file, the application descriptive file having information dependent upon an entity file, which includes software for executing an application, and information showing a storage location of said entity file, the authorization information of the security descriptive file indicating an allowable range of an operation of the application which is executed in accordance with said software, said terminal unit executing operation of the application within the allowable range shown by said authorization information; a dependent information obtaining process for said terminal unit to obtain, by using said first identification information contained in said security descriptive file transmitted from said communication system in said authorization transmission process, said application descriptive file from one or a plurality of server units (12, 13, 14) in which said application descriptive file is stored; and a program obtaining process for said terminal unit to obtain said entity file from said communication system by using said information showing storage location of said entity file and contained in said application descriptive file obtained in said dependent information obtaining process. a process for transmitting an authorization file in a communication system, wherein said process for transmitting includes transmitting through a secure link to a terminal unit a security descriptive file as said authorization file from an administering server unit storing said security descriptive file the security descriptive file containing first identification information and authorization information, the first identification information showing a storage location of an application descriptive file, the application descriptive file having information dependent upon an entity file, which includes software for executing an application, and information showing a storage location of said entity file, the authorization information of the security descriptive file indicating an allowable range of an operation of the application which is executed in accordance with said software, said terminal unit executing operation of the application within the allowable range shown by said authorization information; a dependent information obtaining process for said terminal unit to obtain, by using said first identification information contained in said security descriptive file transmitted from said communication system in said authorization transmission process, said application descriptive file from one or a plurality of server units (12, 13, 14) in which said application descriptive file is stored; and a program obtaining process for said terminal unit to obtain said entity file from said communication system by using said information showing storage location of said entity file and contained in said application descriptive file obtained in said dependent information obtaining process.