Modern cars use CAN-Bus (Controller Area Network). High-quality systems handle (for older VAG cars like the Mk4 Golf) and CAN 2.0B (for 2020+ models). When vagcomhwtypeexe polls a high-quality device, it reports back support for "SW CAN" and "HEX-NET" protocols. Cheap units only report "KWP2000" (obsolete).
In diagnostics, high quality is not a feature—it is a requirement. Do not compromise.
vagcomhwtype.exe (version 1.0) has a known hash of d41d8cd98f00b204e9800998ecf8427e (Note: verify against official sources).