ChaMAILeon: Exploring the Usability of a Privacy Preserving Email Sharing System.

While passwords, by definition, are meant to be secret, recent trends have witnessed an increasing number of people sharing their email passwords with friends, colleagues, and significant others. However, leading websites like Google advise their users not to share their passwords with anyone, to avoid security and privacy breaches. To understand users' general password sharing behavior and practices, we conducted an online survey with 209 Indian participants and found that 64.35% of the participants felt a need to share their email passwords. Further, about 77% of the participants said that they would want to use a system which could provide them access control features, to maintain their privacy while sharing emails. To address the privacy concerns of users who need to share emails, we propose ChaMAILeon, a system which enables users to share their email passwords while maintaining their privacy. ChaMAILeon allows users to create multiple passwords for their email account. Each such password corresponds to a different set of access control rules, and gives a different view of the same email account. We conducted a controlled experiment with 30 participants to evaluate the usability of the system. Each participant was required to perform 5 tasks. Each task corresponded to different access control rules, which the participant was required to set, for a dummy email account. We found that, with a reasonable number of multiple attempts, all 30 participants were able to perform all 5 tasks given to them. The system usability score was found out to be 75.42. Moreover, 56.6% of the participants said that they would like to use ChaMAILeon frequently.