X

X.200

An Open Systems Interconnect (OSI) standard.

See also Open Systems Interconnect.

X.208

The ITU standard defining ASN.1.

X.209

The ITU standard that defines BER encodings for ASN.1 objects.

See also Basic Encoding Rules.

X.400

The ITU standard that defines message tokens.

X.500

The ITU standard that defines the structure of a global dictionary.

X.509

The ITU standard that defines the structure of an X.509 public-key certificate. Also available as ISO/IEC 9594-8.

X.509 certificate

A standard certificate defined in the ITU-T recommendation X.509. An X.509 certificate includes information about the person or entity to whom the certificate is issued, information about the certificate, plus optional information about the CA issuing the certificate.

Subject information may include the entity's name, public key, public-key algorithm, and an optional unique subject ID.

X509_ASN_ENCODING

Specifies certificate encoding. Certificate encoding types are stored in the low-order word of a DWORD (value is: 0x00000001).

Functionally the same as CRYPT_ASN_ENCODING.

XOR

Exclusive OR. A Boolean operation that yields true only if one of its operands are true and the other is false. If both operands are the same (either True or False), the operation yields false.