ip2region is an offline IP geolocation library and framework designed to resolve IPv4 and IPv6 addresses to city-level regional information using local binary data files. It functions as a binary IP database compiler and a cross-language search client, allowing for regional lookups without relying on external APIs.
The project distinguishes itself through a specialized binary format that supports high-performance query optimization. It employs adjacent-segment IP merging and deduplicated region storage to minimize the database footprint, while utilizing memory-mapped file caching and vector-index search mechanisms to achieve microsecond-level response times.
The framework covers comprehensive IP data management, including the ability to compile, edit, and validate raw localization records. It provides tools for building custom geolocation datasets with business-specific metadata and offers flexible caching configurations to balance memory consumption against lookup speed.
The library includes search implementations for multiple programming languages and supports integration with Nginx for request processing.
