The Windows binaries are available in two variants. a) Default. This is what people usually use. This version of library is included in Apache Tomcat distributions. b) OCSP-enabled. This one has enabled (experimental) support for verification of client SSL certificates via OCSP protocol (45392).
Each archive contains tcnative-1.dll for 32-bit and 64-bit (x64) CPU architectures. You have to use the DLL that matches CPU architecture of JVM that you use to run Tomcat.
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