Electronic trust service of validation of the status of a qualified public key certificate in real time (OCSP) according to the algorithm of DSTU 4145-2002 "Information technologies. Cryptographic protection of information. A digital signature based on elliptic curves. Creation and validation" and/or international RSA or ECDSA algorithms defined by DSTU ETSI TS 119 312:2022 (ETSI TS 119 312 V1.4.2 (2022-02), IDT) "Electronic signatures and infrastructures (ESI). Cryptographic suits".