VisualSec: A Secure Message Delivery Scheme for Online Social Networks Based on Profile Images

With rapid growth of Online Social Networks (OSN), more and more users are attracted to share their personal information or even cooperate in business via OSN. Therefore, the issues of privacy and security in OSN become more important than ever. In this paper, we address the issue of securely delivering message through OSN. A secure message delivery scheme based on profile images, called VisualSec, is proposed. One of the main differences between our scheme and existing schemes is that we utilize visual identifier, i.e., profile image which is common in OSN, as the public key. Furthermore, the proposed scheme does not depend on a single trusted authority (or multiple trusted authorities), instead, it is a fully distributed scheme exploiting social relationships formed by OSN to provide authentication and key generation services. With a profile image, one could encrypt and deliver messages which could only be decrypted by the user who is identical to that image. The implementation issues as well as the efficiency and security of VisualSec are discussed and evaluated in this paper. It is illustrated that the proposed scheme is a feasible and efficient solution for delivering message securely through OSN.