A method and system for detecting a spam over internet telephony (SPIT) is disclosed. Incoming call requests are received and analyzed using heuristic algorithms. A runtime action is provided based on the analysis using the heuristic algorithms. The heuristic algorithms include zero-touch heuristic algorithms that require no human intervention, one-touch heuristic algorithms that require human intervention one time, and multi-touch heuristic algorithms that require human intervention more than one time. Cumulative probability is calculated for each incoming call request, and the incoming call request is classified as a spam if the cumulative probability exceeds a threshold.