Since he joined CNNIC in 2003, YAO Jian-kang had been mainly engaged in the researches of internationalized domain name, internationalized e-mail and DNS technology. In international Internet technology organization IETF, he was once the Co-Chair of Applications Area Working Group (APPSAWG), secretary of the working group of E-mail Address Internationalization (EAI), and a member of Applications Director Committee (APPSDIR). In international Internet organization ICANN (Internet Corporation for Assigned Names and Numbers), as a member of the working group of International Data, he is also one of the seven global representatives of the Internet community selected by ICANN to have access to the global DNSSEC root key, and is the first author of RFC5336 and RFC6531.