The invention discloses a
ciphertext graph K-hop
reachability rapid query method supporting
privacy protection, and aims to solve the limitation in a traditional
spanning tree K-hop query scheme, including that nodes only belong to a small number of spanning trees, a large number of node pairs need to be realized through cross-tree query, non-tree edges are recursively traversed by depending on an
adjacency list, and the efficiency is very low; and no clear path starting point guidance exists in root node selection, so that the coverage range of the
spanning tree is dispersed, and the maximum coverage capability is insufficient. And a high-coverage, high-security and high-efficiency
ciphertext graph K-hop
reachability rapid query method supporting
privacy protection is designed. The multi-round root node BFS
spanning tree and circular
pruning collaborative method is provided, the efficiency
bottleneck of frequent
recursion operation during cross-spanning tree K-hop query of a traditional graph is solved, and an
accessibility result can be quickly researched and judged through intersection operation of spanning tree sets where starting and ending points are located; besides, a node-spanning tree and spanning tree-node triple efficient
ciphertext index architecture is constructed by fusing cryptographic technologies such as
homomorphic encryption and order-preserving
encryption, so that double breakthrough of efficiency and security of K-hop
reachability query of the ciphertext DAG is realized, and a new technical approach and solution are provided for privacy-protected graph
data processing.