  In ubiquitous computing domain context awareness is an important issue. So,
in ubiquitous computing, mere protection of message confidentiality is not
sufficient for most of the applications where context-awareness can lead to
near deterministic ideas. An adversary might deduce sensitive information by
observing the contextual data, which when correlated with prior information
about the people and the physical locations that are being monitored by a set
of sensors can reveal most of the sensitive information. So, it is obvious that
for security and privacy preservation in ubiquitous computing context
protection is of equal importance. In this paper, we propose a scheme which
provides two layer privacy protection of user's or application's context data.
Our proposed context protecting privacy preservation scheme focuses on
protecting spatial and temporal contextual information. We consider the
communication part of ubiquitous computing consists of tiny sensor nodes
forming Wireless Sensor Networks (WSNs). Through simulation we show the
efficacy of our scheme. We also demonstrate the capability of our scheme to
overcome the constraints of WSNs.
