Date Added: Aug 2013
A Wireless Sensor Network (WSN) commonly requires lower level security for public information gathering, whilst a Body Sensor Network (BSN) must be secured with strong authenticity to protect personal health information. In this paper, some practical problems with the Message Authentication Codes (MACs), which were proposed in the popular security architectures for WSNs, are reconsidered. The analysis shows that the recommended MACs for WSNs, e.g., CBC- MAC (TinySec), OCB-MAC (MiniSec), and XCBC-MAC (SenSec), might not be exactly suitable for BSNs. Particularly an existential forgery attack is elaborated on XCBC-MAC.