MobileCA: Accumulative secure group association with a certification path

In recent years, there has been growing interest in secure pairing, which refers to the establishment of a secure connection between two mobile devices. Many published studies have described the various types of out-of-band (OOB) channels through which authentication data can be transferred with user control and involvement. However, there has been little discussion of setting up secure connections between groups of mobile devices. Some security protocols have been proposed, but they have tended to focus on a scenario whereby all devices must be located in one place to perform the association. In this paper, we describe a new group association method, called MobileCA. Our method is designed for a broader range of scenarios and does not require all devices to be in one place at one time. MobileCA extends the OOB channel concept and utilizes digital certification. We have implemented a prototype system using smart phone handsets.