21Vianet Group Inc is a carrier-neutral internet data center services provider in China. It provides managed network services to enable customers to deliver data across the internet in a reliable manner through its data transmission network. It also offers value-added services, such as VPN (virtual private network) services, CDN (content delivery network) services and last-mile wired broadband services to improve the security, speed, and quality of data transmission. The company operates through one segment Hosting and related services. It generates all of its revenue from China.