Signature-Based Top-k Query Processing against Data Replacement Attacks in MANETs

In this paper, we propose a signature-based top-k query processing method against data replacement attacks in mobile ad hoc networks (MANETs). In order to rapidly identify a greater number of malicious nodes, nodes share information about identified malicious nodes with other nodes. If nodes share only this information, however, malicious nodes may successfully transmit false information identifying normal nodes as malicious. Therefore, in the proposed method, when nodes send reply messages during query processing, they attach encrypted information about the sent data items (i.e., digital signatures), providing the query-issuing node with critical information about the data items sent by nodes in the network, and thereby enabling it to identify malicious nodes, using the received signatures. After identifying the malicious nodes, it floods the network with a notification message including the signatures in which the identified malicious nodes have replaced higher-score data items to their own lower-score items.