Abstract: Photo sharing is an attractive feature which popularizes Online Social Networks (OSNS). Unfortunately, it may leak users’ privacy if they are allowed to post, comment, and tag a photo freely. We attempt to address this issue and study the scenario when a user shares a photo containing individuals other than him/her. To prevent possible privacy leakage of a photo, we design a mechanism to enable each individual in a photo be aware of the posting activity and participate in the decision making on the photo posting. For this purpose, we need an efficient facial recognition (FR) system that can recognize everyone in the photo.We also develop a distributed consensusbased method to reduce the computational complexity and protect the private training set. We show that our system is superior to other possible approaches in terms of recognition ratio and efficiency.

Keywords: Photograph protection, Social media, Secure Multi Calculation, Facial RecognitionAuthentication, honeypot, honeywords, login, passwords, password cracking.