Computer product, search method, search apparatus, and node

摘要

Nodes respectively store a multilayer transposed Bloom filter. A client selects a node N1 from among the group of nodes and transmits a search request to the node N1. Upon receiving a reply from the node N1, the client determines whether the received search result indicates “positive”. If the search result is not positive, the client selects in order of node number, a node N2 and transmits a search request to the node N2. Upon receiving a reply from the node N2, the client determines whether the received search result indicates “positive”. Upon determining that the search result is positive, the client outputs the search result and ends the search notification process.

主权项

1. A non-transitory computer-readable medium storing therein a search program that causes a transmission source computer to execute a method the method comprising:
accessing a node group; storing, in each node of the node group, a data structure having a multilayer transposed Bloom filter that is transposed by gathering, at each level, bits at identical positions in each Bloom filter constituting a Bloom filter row in a multilayer Bloom filter having a level count h, a bit width s, a divisor d of an h-th level of arranged bits indicating false positive or negative, a p-th (1≦p≦h) level Bloom filter bit width m=s/d[h−(p−1)] and a p-th level Bloom filter count n=d[h−(p−1)], the data structure further having a data block set corresponding to a first level Bloom filter row of the multilayer Bloom filter and each node further executing processing that involves using the multilayer transposed Bloom filter to determine whether search data is present in the data block set and transmitting to the transmission source computer of the search data, a search result indicating whether the search data is present; selecting from the node group, an unselected node; transmitting the search data to the selected node; receiving the search result from the selected node; determining whether the received search result indicates the search data to be present; and outputting a determination result, wherein any one among the level count h, the bit width s, and the divisor d differs between at least two nodes among the node group.