K-reach : who is in your small world

• Main Authors: Cheng, James, Shang, Zechao, Cheng, Hong, Wang, Haixun, Yu, Jeffrey Xu
• Other Authors: School of Computer Engineering
• Format: Article
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Computer science and engineering
• Online Access: https://hdl.handle.net/10356/102236; http://hdl.handle.net/10220/18931; http://dl.acm.org.ezlibproxy1.ntu.edu.sg/citation.cfm?id=2350247&dl=ACM&coll=DL
• Institution: Nanyang Technological University

We study the problem of answering k-hop reachability queries in a directed graph, i.e., whether there exists a directed path of length k, from a source query vertex to a target query vertex in the input graph. The problem of k-hop reachability is a general problem of the classic reachability (where k = ∞). Existing indexes for processing classic reachability queries, as well as for processing shortest path queries, are not applicable or not efficient for processing k-hop reachability queries. We propose an index for processing k-hop reachability queries, which is simple in design and efficient to construct. Our experimental results on a wide range of real datasets show that our index is more efficient than the state-of-the-art indexes even for processing classic reachability queries, for which these indexes are primarily designed. We also show that our index is efficient in answering k-hop reachability queries.