A secure and traceable E-DRM system based on mobile device Chin-Ling Chen * Department of Computer Science and Information Engineering, Chaoyang University of Technology, Taichung 41349, Taiwan, ROC. E_mail:clc@mail.cyut.edu.tw. Abstract In recent years, intellectual property violation events have caused enterprise to respect digital content protection. Illegal copying digital content abuses become a serious problem. Because the mobile devices are more portable and individualized than personal computers, anyone can access the network resources at anytime from anywhere. However, valuable digital contents without proper protection make the content vulnerable to unauthorized copying, modification and re-distribution, causing revenue losses to service providers. Thus, constructing an effective Digital Right Management (DRM) system has become an important issue. On the basis of the mobile device, we propose an efficient digital rights management protocol. We apply symmetrical cryptosystem, asymmetrical cryptosystem, digital signature and one-way hash function mechanisms in our scheme. To overcome * Corresponding author. E-mail address: clc@mail.cyut.edu.tw (Chin-Ling Chen)