DAD (Decentralized Advertising) as a new generation of digital advertising chain, has been actively applied to digital advertising since 2013. Today, it has a total of 500 million users, with tens of billions of daily ad displays in 194 countries and communities worldwide. We've provided services to 110K+ advertisers, including Baidu, Alibaba, Meitu, 360, Uber, Toutiao, Huobi, OKEx, and Cobo Wallet, etc. After years in the advertising industry, DAD has established a huge amount of precise user labels, customized AI algorithms, abundant ad scenarios, as well as special ad review and anti-scam algorithms. In 2017, DAD has established strategic cooperation with Ontology and conducted in-depth reform in the advertising industry via the blockchain technology, and resolved problems that frequently occur in the traditional advertising industry, such as users not in control of their own private data, and ad data is not open and transparent, which manifests as fake traffic, privacy leaks, and trust issues. After applying the blockchain technology, users have total control of their private information and can decide what kind of ads they want to receive, thus reshaping advertising ecology.