21cn.com, the fifth largest email service provider on the Chinese mainland, has adopted a next-generation anti-spam system called Knowledge-based Anti-spam Gateway from Hanqi Technology.

Shenzhen-based Hanqi Technology, who reportedly beat two foreign competitors in a strict selection process held by 21cn, regards the victory as an important milestone showing that Chinese anti-spam technologies can perform as well as foreign counterparts. 21cn says it chose KBAS because it works better when using the Chinese language and it is more suitable for China's email system environment.

Excessive unsolicited bulk email is a major problem for China's technology industry, with international anti-spam group Spamhaus ranking China second in the world as a top origin for global spam.

According to 21cn, KBAS introduces the concept of "Expert Repository". By combining the email observation and analysis process, it simulates the entire process in which email professionals identify spam and analyze emails in an intellectual way, which has greatly increased the rate of blocking spam. Tests show that it can block 98% of all Chinese-language spam. In addition, email receivers are now better able to report spam. This function provides an effective way for email users who hate spam but can't do anything about it. The spam block rate of the system can reportedly also reach 100% with receivers' participation. Finally, it allows email senders to complain when their emails are mistakenly identified as spam. The real-time content filtering function and the special anti-disturbance analysis technology of the system makes sure that users can smoothly use the email service.

The system adopts a content filtering pattern and has potential for integrating more semantic and heuristic analyses.