text: We introduce Pixie, a novel, camera based two factor authentication solution for mobile and wearable devices. A quick and familiar user action of snapping a photo is sufficient for Pixie to simultaneously perform a graphical password authentication and a physical token based authentication, yet it does not require any expensive, uncommon hardware. Pixie establishes trust based on both the knowledge and possession of an arbitrary physical object readily accessible to the user, called trinket. Users choose their trinkets similar to setting a password, and authenticate by presenting the same trinket to the camera. The fact that the object is the trinket, is secret to the user. Pixie extracts robust, novel features from trinket images, and leverages a supervised learning classifier to effectively address inconsistencies between images of the same trinket captured in different circumstances. Pixie achieved a false accept rate below 0.09 in a brute force attack with 14.3 million authentication attempts, generated with 40,000 trinket images that we captured and collected from public datasets. We identify master images, that match multiple trinkets, and study techniques to reduce their impact. In a user study with 42 participants over 8 days in 3 sessions we found that Pixie outperforms text based passwords on memorability, speed, and user preference. Furthermore, Pixie was easily discoverable by new users and accurate under field use. Users were able to remember their trinkets 2 and 7 days after registering them, without any practice between the 3 test dates.
  @cite_62: Wearable computing devices have become increasingly popular and while these devices promise to improve our lives, they come with new challenges. This paper focuses on user authentication mechanisms for the Google Glass device (Glass). Glass only has three sources of input: a camera, a microphone, and a touchpad. This limited set of interfaces makes the use of standard passwords infeasible or cumbersome. We therefore propose a One-Time-Password (OTP) authentication scheme, Glass OTP that uses the Glass camera to scan a QR code displayed on the user’s smartphone. We implement a proof of concept Glass lock screen which unlocks only upon scanning an OTP generated by the companion Android smartphone application. We also discuss the reliability, security, and convenience of the proposed solution as compared to the current solutions in use.
  @cite_49: Smartwatches can facilitate several tasks that are performed on mobile devices. However, due to their limited size, touch interaction can be cumbersome. Although alternative input modalities such as speech input could be used, these can also introduce other issues regarding privacy or ease of use. Consequently, HCI researchers have been exploring novel input techniques for smartwatches. In this paper, we introduce WatchMe, a smartwatch application that uses the smartwatch camera and image processing techniques to allow for providing input on a drawing canvas composed of everyday objects and surfaces. We rely on a cloud OCR engine to retrieve text from captured images. Combining these characteristics, we illustrate some scenarios in which WatchMe could be used, such as a novel method for two-factor authentication.
  @cite_39: Credit card fraud is a common problem in today's world. Financial institutions have registered major loses till today due to users being exposed of their credit card information. Shoulder-surfing or observation attacks, including card skimming and video recording with hidden cameras while users perform PIN-based authentication at ATM terminals is one of the common threats for common users. Researchers have struggled to come up with secure solutions for secure PIN authentication. However, modern day ubiquitous wearable devices, such as the Google Glass have presented us with newer opportunities in this research area. In this paper, we propose Secure-PIN-Authentication-as-a-Service (SEPIA), a secure obfuscated PIN authentication protocol for ATM and other point-of-service terminals using cloud-connected personal mobile and wearable devices. Our approach protects the user from shoulder-surfers and partial observation attacks, and is also resistant to relay, replay, and intermediate transaction attacks. A SEPIA user utilizes a Google Glass or a mobile device for scanning a QR code on the terminal screen to prove co-location to the cloud-based server and obtain a secure PIN template for point-of-service authentication. SEPIA ensures minimal task overhead on the user's device with maximal computation offloaded to the cloud. We have implemented a proof-of-concept prototype to perform experimental analysis and a usability study for the SEPIA architecture.
summary: Similar to Pixie, cameras integrated in wearable devices have been used to capture the input for authentication. Van @cite_49 exploit the smartwatch camera to provide the device with an input (e.g. PIN) that is drawn on a canvas, then use image processing techniques to interpret the captured input. @cite_62 propose to pair and unlock smartglasses with the user smartphone by exploiting the glass camera to scan a QR code that is displayed on the user's phone screen. Similarly, @cite_39 use the smartglass camera to scan a QR code that is displayed on a point-of-service terminals (e.g. ATM) to connect to a cloud server for obtaining an OTP.