GeoIP2-CN provides curated datasets and binary database files designed to identify network addresses originating from mainland China. It provides a GeoIP2 China database and a routing list formatted as a MaxMind compatible database for use with network tools.
The project enables proxy traffic management by distinguishing between domestic and international IP addresses. This allows for regional network routing and the application of decision logic to separate traffic paths based on geographic location.
The system implements IP identification through MMDB-based lookups, binary-search range matching, and CIDR-list filtering. It also supports connecting proxy tools to these databases via external URL mapping.