Abstract: VoIP is an important application in next generation convergence network, and SIP is a key application protocol of VoIP. However, the SIP-based applications are facing to lots of challenges to information security, such as spam over Internet telephony (SPIT), since VoIP is sensitive to time delays and very difficult to understand the Internet messages correctly and rapidly and SPIT is hard to detect. To solve this problem, the architecture of the solution to SPIT detection/prevention based on domain verification is designed with the SIP amelioration in PULL mode and pre-classification cooperation both described for SPIT filtration/detection. The implementation and verification results reveal that the solution can provide an effective means for SPIT rejection.