RKN Block Checker
Diagnose RKN/TSPU internet blocks layer by layer (DNS, TCP, TLS, HTTP)
RKN Block Checker is a small Python CLI for diagnosing whether the current network connection is affected by Russian RKN or TSPU blocking. It tests blocking behavior layer by layer instead of only reporting that a site is unreachable. The tool can help distinguish DNS poisoning, TCP reset behavior, TLS DPI based on SNI, and ISP stub pages. This makes it useful for developers, system administrators, network researchers, and censorship-measurement workflows. It is designed as a console utility with straightforward installation and optional proxy support. Its main value is giving users a structured way to understand what kind of network interference is occurring rather than relying on vague connectivity symptoms.