Improvement of Secure Communication Method Using Secret Sharing Schemes over MANET

A Mobile Ad-hoc Network (MANET) has been studied in order to realize a ubiquitous society. However, MANET has many issues. One of the issues is security. For example, MANET is vulnerable to network sniffing because it is using a wireless communication that can be heard by others and existing security approaches are difficult to be applied to it. For the purpose, we have already proposed a novel secure communication method using secret sharing schemes over MANET. In this paper, we study how to enhance the security of the original proposal and propose an improvement by which restoring the secret by malicious user is very hard to be executed. We evaluate the improved method from the viewpoints of difficulty in restoration of key shares and show its effectiveness.