Internet group Alibaba has launched an online service to match advertisers with China's small and medium-sized websites and bloggers, the Financial Times reported. The company will take a commission of around 8% for advertising sales made through the site. It claims to have signed up over 150,000 small and medium-sized web publishers and 135,000 personal blogs since August. The service is seen as a direct challenge to Baidu.com, the internet search engine, which operates its own "website alliance" advertising exchange. Alibaba already competes with Baidu on search through its Yahoo China unit, and Baidu has announced plans to set up a consumer-to-consumer service expected to challenge Alibaba's online auction business. Alibaba's e-commerce unit, Alibaba.com, recently raised US$1.5 billion in Hong Kong share listing.