X.692: Information technology - ASN.1 encoding rules: Specification of Encoding Control Notation (ECN)
Recommendation ITU-T X.692 | ISO/IEC 8825-3 defines the Encoding Control Notation (ECN) used to specify encodings (of ASN.1 types) that differ from those provided by standardized encoding rules such as the Basic Encoding Rules (BER) and the Packed Encoding Rules (PER).