Communication device and communication method for processing meta data

A communication device connected to a network, the communication device comprising:

• a receiver configured to receive meta data that includes attribution information of data and access information of the data;
• a storage configured to store the meta data received by the receiver;
• and
• a processor configured to
• extract a keyword from the attribution information that is included in the meta data and store, in the storage, index information in which the keyword and information for identifying the meta data are associated with each other;
• and
• transmit, to a participating node via the network, a stop request that is a request to stop a transmission of meta data when an amount of the index information stored in the storage is larger than or equal to a specified threshold, and wherein the stop request makes a request to stop a transmission of meta data and makes a request to transmit data amount information that indicates an amount of data that participating node has provided to the network after the stop request was transmitted to the participating node.

A communication method to be used in a communication system that includes first and second communication devices connected over a network, wherein

• the first communication device
• receives meta data that includes attribution information of data and access information of the data,
• stores the meta data in a first storage,
• extracts a keyword from the attribution information that is included in the meta data,
• stores, in a second storage, index information in which the keyword that is extracted from the attribution information and information for identifying the meta data are associated with each other, and
• transmits, to the second communication device and a participating node in the network, a stop request that is a request to stop a transmission of meta data when an amount of the index information stored in the second storage is larger than or equal to a specified threshold,
• the second communication device
• before receiving the stop request from the first communication device, transmits, to the first communication device, meta data that corresponds to data provided to the network via the second communication device, and
• after receiving the stop request from the first communication device, stops a transmission of meta data to the first communication device and transmits, to the first communication device, data amount information indicating an amount of data provided to the network via the second communication device after the stop request was received, and
• the first communication device
• associates the data amount information with information for identifying the second communication device and records the data amount information and the information for identifying the second communication device,
• when the index information stored in the second storage includes a search keyword input by a user, acquires meta data that corresponds to the search keyword from the first storage and provides the acquired meta data to the user, and
• when the index information stored in the second storage does not include the search keyword, transmits a search request to perform a search with the search keyword to a participating node specified according to the data amount information.