X.509

x.509 is a type of digital certificate, like an ID card that proves who you are. It is used to help you prove your identity to someone else, like a website or other computer. It holds information about who you are and is signed by someone who makes sure it is valid so the other person can trust it. It can also be used to send encrypted messages so nobody else can read them.

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Abstract Syntax Notation One, Certificate policy, Code Access Security, Communications security, EdDSA, ISO/IEC JTC 1, Information security, PKI Resource Query Protocol, Public-key cryptography, Public Key Infrastructure, Time stamp protocol, Trusted timestamping