It is very probable that VoIP will soon replace the ordinary telephone. Beside all advantages of the digital voice-connection it is linked to the danger of spam on the telephone. A lot of approaches have been developed to solve the problem of VoIP spam. Because some of these solutions are based on access to personal information of its users, a broad discussion about the best and most ethical approach has started.

This thesis analyzes the users’ point of view towards the VoIP spam problem and the extent of users’ willingness to offer private information in order to avoid VoIP spam. It presents results from a qualitative and a quantitative research as well as approaches for a most realistic- and most promising VoIP solution. These new approaches are based on the results of the research.

The main points of the results showed that users were not willing to offer private information to companies and that they were not willing to pay any amount of money for VoIP spam solutions. Users held governmental organisations and telephone operators responsible for finding a solution against VoIP spam.