Date of Original Version



Technical Report

Abstract or Description

Users regularly experience a crisis of confidence on the Internet. Is that email or instant message truly originating from the claimed individual? Such doubts are commonly resolved through a leap of faith, expressing the desperation and helplessness of users.

To establish a secure basis for online communication, we propose SafeSlinger, a system leveraging the proliferation of smartphones to enable people to securely and privately exchange their public keys. Through the exchanged authentic public keys, Safe- Slinger establishes a secure channel offering secrecy and authenticity, which we use to support secure messaging and file exchange. SafeSlinger also provides an API for importing applications’ public keys into a user’s contact information. By slinging entire contact entries to others, we propose secure introductions, as the contact entry includes the SafeSlinger public keys as well as other public keys that were imported. We present the design and implementation of SafeSlinger for Android and iOS, which is available from the respective app stores. An overview video of SafeSlinger is available at: