A communication device, comprising: an IC chip storing information in a predetermined area and functioning as a reader/writer that is configured to read out or write information about an item from or to another IC chip, respectively, the information about an item being stored in the other IC chip in a predetermined area; means for downloading an agent from an information processing device connected to the network, where said agent is provided as an application software operating said IC chip as a reader/writer; means for acquiring URL provided for accessing said information processing device to download a role, wherein said URL includes parameters described therein and used in processing of determining whether said information processing device allows said communication device to download said role, means for transmitting a request for acquiring a role-download activation page to said information processing device based on said URL, wherein on the basis of information included in said request for acquiring said role-download activation page, a GUI screen is displayed based on display data of said role-download activation page transmitted from said information processing device when said information processing device allows said communication device to download said role, means for downloading a role from said information processing device connected to the network using said agent downloaded therefrom, where said role is provided as script data in which part of the contents of processing of said reader/writer performed by said agent is described, the processing depending on the item stored in the other IC chip, wherein said agent is activated to allow said means for downloading said role to download said role when said link in said GUI screen is operated, the agent transmitting a role-download request to a role server of the information processing device, the role-download request comprising a download key and an agent ID, and receiving the role from the role server if the download key and the agent ID are valid; means for activating said agent to allow said IC chip to perform said processing of said reader/writer, including transmitting predetermined check information to said information processing device connected to said network, said agent being activated based on a check result transmitted from said information processing device; and means for activating said role, to allow said IC chip to perform said processing of said reader/writer, including transmitting predetermined check information to said information processing device connected to said network, said role being activated based on a check result transmitted from said information processing device. an IC chip storing information in a predetermined area and functioning as a reader/writer that is configured to read out or write information about an item from or to another IC chip, respectively, the information about an item being stored in the other IC chip in a predetermined area; means for downloading an agent from an information processing device connected to the network, where said agent is provided as an application software operating said IC chip as a reader/writer; means for acquiring URL provided for accessing said information processing device to download a role, wherein said URL includes parameters described therein and used in processing of determining whether said information processing device allows said communication device to download said role, means for transmitting a request for acquiring a role-download activation page to said information processing device based on said URL, wherein on the basis of information included in said request for acquiring said role-download activation page, a GUI screen is displayed based on display data of said role-download activation page transmitted from said information processing device when said information processing device allows said communication device to download said role, means for downloading a role from said information processing device connected to the network using said agent downloaded therefrom, where said role is provided as script data in which part of the contents of processing of said reader/writer performed by said agent is described, the processing depending on the item stored in the other IC chip, wherein said agent is activated to allow said means for downloading said role to download said role when said link in said GUI screen is operated, the agent transmitting a role-download request to a role server of the information processing device, the role-download request comprising a download key and an agent ID, and receiving the role from the role server if the download key and the agent ID are valid; means for activating said agent to allow said IC chip to perform said processing of said reader/writer, including transmitting predetermined check information to said information processing device connected to said network, said agent being activated based on a check result transmitted from said information processing device; and means for activating said role, to allow said IC chip to perform said processing of said reader/writer, including transmitting predetermined check information to said information processing device connected to said network, said role being activated based on a check result transmitted from said information processing device.