Comments on "Accountable and Privacy-Enhanced Access Control in Wireless Sensor Networks"
In a recent paper (IEEE Trans. Wireless Commun., vol. 14, no. 1, 2015), He et al. proposed an accountable and privacy-enhanced access control (APAC) protocol, which aimed to provide privacy for honest users against network owners and accountability against misbehaving users without the involvement of any trusted third party. However, the level of trust on the network owner has not been clearly defined in He et al.'s paper, and we demonstrate in this letter that in the case where the network owners cannot be trusted to correctly generate the system parameters, then the APAC protocol cannot ensure user privacy.