Analysis of spam over Internet telephony protection techniques

Spam in Internet telephony networks is likely to become a large problem in the future, as more and more people and companies switch from traditional telephone networks to Voice over IP (VoIP) networks. VoIP spam is likely to have a great strain on the network. The question that will be answered in with this research is: “What methods exist against spam over Internet Telephony and which technique or combination of techniques is the most promising for the future?”. Therefore, we identify techniques to prevent and reduce spam in VoIP networks that exist today. These techniques are analyzed for their advantages and disadvantages and on how they comply with criteria that spam protection techniques have to meet. We also identify some combinations of techniques that would complement each other. This will provide an overview that can be used for other research on the topic of VoIP spam. We identified a technique that is suitable for use, memory bound functions. In addition, a combination of this technique with whitelisting or handshake/challenge/Turing tests with whitelisting or signalling protocol analysis with whitelisting are suitable for use as protection techniques against VoIP spam.