A personal network (PN) should enable the collaboration of user's devices and services in a flexible, self-organizing, and friendly manner. For such purpose, the PN must securely accommodate heterogeneous technologies with uneven computational and communication resources. In particular, personal radio frequency identification (RFID) tags can enable seamless recognition of user's context, provide user authentication, and enable novel services enhancing the quality and quantity of data handled by the PN. However, the highly constrained features of common RFID tags and their passive role in the network highlights the need of an adequate secure communication model with personal tags, which enables their participation as a member of the PN. In this paper, we present our concept of PN, with special emphasis on the role of RFID and sensor networks, and define a secure architecture for PNs including methods for the secure access to context-aware technologies from both local PN members and the Internet of Things. The PN architecture is designed to support differentiated security mechanisms to maximize the level of security for each type of personal device. Furthermore, we analyze which security solutions available in the literature can be adapted for our architecture, as well as the challenges and security mechanisms still necessary in the secure integration of personal tags. Copyright © 2013 John Wiley & Sons, Ltd.