Dealing with Telephone Fraud Using CAPTCHA

Nowadays mobile communication permeates daily life everywhere. So as the troubles made by spam SMS (Short Message Service), telephone frauds are also obsessing the users. In this paper a new method is proposed for avoiding telephone frauds using CAPTCHA (completely automatic public turing test to tell computer and human apart) systems. In this method, an authorize code is structured and decomposed into several parts. After dealing with the parts separately an animation authorize code is generated with these parts as its frames. The animation authorize code is sent as a SMS multimedia message to the one who is calling in. The caller should type the authorize code correctly and send the code back as a short message in reply. If the caller can pass the CAPTCHA test, it will be identified that the call is not a fraud.