Information processing device, recording medium storing information search program, and information search method

A non-transitory computer-readable recording medium having stored therein a program for causing an information processing device to execute a process, the information processing device being any of a plurality of information processing devices to be connected in a manner capable of mutually communicating via a communication network, each of the plurality of information processing devices having any of hash values associated with a hash space based on distribution hash information providing the hash values according to a distributed hashing method, the process comprising:

• acquiring access information for requesting access to a target information processing device from among the plurality of information processing devices, the information processing device storing first distribution hash information and second distribution hash information, the plurality of information processing devices being divided into a plurality of groups according to the hash values associated with the hash space, the first distribution hash information representing distribution hash information relying on a hash value in the hash space of a first device that is any of the plurality of information processing devices belonging to any of the plurality of groups, the second distribution hash information representing distribution hash information relying on a hash value in the hash space of one or more second devices that are an information processing devices belonging to a group to which the first device belongs, the access information being transmitted from a client device or another information device on the basis of the first distribution hash information stored by the client device or the another information processing device, the access information including a first hash value generated using a hash function from an identifier identifying each of the plurality of information processing devices;
• extracting the first hash value from the access information;
• searching the second distribution hash information for the one or more second devices corresponding to the extracted first hash value;
• and
• transmitting the access information to a retrieved second device by the searching;
• when a participation request to a first group to which the first device belongs is issued from the information processing device that does not belong to any of the groups, comparing the number of the one or more second devices belonging to the first group with a prescribed threshold;
• selecting a second device of the one or more second devices according to a result of the comparison;
• separating, from the first group, one or more second devices having the hash value included in a range from a starting point of the hash space corresponding to the first group to the hash value of the selected second device;
• generating the second distribution hash information pertaining to the group formed by the separated one or more second devices;
• and
• adding the selected second device to the first distribution hash information.

An information search method of accessing a target information processing device of a plurality of information processing devices in an information processing system including the plurality of information processing devices being connected in a manner capable of communicating with each other via a communication network, each of the plurality of information processing devices having any of hash values associated with a hash space based on distribution hash information providing the hash values according to a distributed hashing method, the information search method comprising:

• acquiring, by an information processing device among the plurality of information processing devices, access information for requesting access to the target information processing device from among the plurality of information processing devices, the any information processing device storing first distribution hash information and second distribution hash information, the plurality of information processing devices being divided into a plurality of groups according to the hash values associated with the hash space, the first distribution hash information representing distribution hash information relying on a hash value in the hash space of a first device that is any of the plurality of information processing devices belonging to any of the plurality of groups, the second distribution hash information representing distribution hash information relying on a hash value in the hash space of one or more second devices that are an information processing devices belonging to a group to which the first device belongs, the access information being transmitted from a client device or another information device on the basis of the first distribution hash information stored by the client device or the another information processing device, the access information including a first hash value generated using a hash function from an identifier identifying each of the plurality of information processing devices;
• extracting, by the information processing device, the first hash value from the access information;
• searching, by the information processing device that acquires the access information, the second distribution hash information for the one or more second devices corresponding to the extracted first hash value, and
• transmitting, by the information processing device that acquires the access information, the access information to a retrieved second device by the searching;
• when a participation request to a first group to which the first device belongs is issued from the information processing device that does not belong to any of the groups, comparing, by the information processing device that acquires the access information, the number of the one or more second devices belonging to the first group with a prescribed threshold;
• selecting, by the information processing device that acquires the access information, a second device of the one or more second devices according to a result of the comparison;
• separating, by the information processing device that acquires the access information, from the first group, one or more second devices having the hash value included in a range from a starting point of the hash space corresponding to the first group to the hash value of the selected second device;
• generating, by the information processing device that acquires the access information, the second distribution hash information pertaining to the group formed by the separated one or more second devices;
• and
• adding, by the information processing device that acquires the access information, the selected second device to the first distribution hash information.