The ip address used by the users of Education Network (most colleges and universities) is ipv6, which is generally fast and suitable for playing pt. However, the home broadband provided by China Telecom, China Unicom and China Mobile is generally ipv4, and ipv6 sites are inaccessible. Famous sites only support six-dimensional ipv6 sites, Beiyou people, but now many sites support ipv6 and ipv4, such as chd.