University of Calgary
With the spread of mobile phones, through Wi-Fi and 3G communications, users have increased opportunities to retrieve messages and files posted by others while on the move, e.g. walking in the Mall, driving the car, etc. For safety, messages are often encrypted and the source is authenticated via PKI, preventing repudiation. Yet, at times the mobile may issue a message that is not accurate either innocently or maliciously. For example, the driver may report rocks on the pavement when there are crossing animals.