The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

OPC 10000-1, OPC Unified Architecture - Part 1: Overview and Concepts

OPC 10000-2, OPC Unified Architecture - Part 2: Security Model

OPC 10000-3, OPC Unified Architecture - Part 3: Address Space Model

OPC 10000-4, OPC Unified Architecture - Part 4: Services

OPC 10000-5, OPC Unified Architecture - Part 5: Information Model

OPC 10000-6, OPC Unified Architecture - Part 6: Mappings

OPC 10000-7, OPC Unified Architecture - Part 7: Profiles

OPC 10000-9, OPC Unified Architecture - Part 9: Alarms and Conditions

OPC 10000-12, OPC Unified Architecture - Part 12: Discovery and Global Services

OPC 10000-18, OPC Unified Architecture - Part 18: Role-Based Security

OPC 10000-21, OPC Unified Architecture - Part 21: Device Onboarding

XML Schema Part 2: XML Schema Part 2: Datatypes

SOAP Part 1, SOAP Version 1.2 Part 1: Messaging Framework

WS Addressing, Web Services Addressing (WS-Addressing)

TLS, RFC 8446 – The Transport Layer Security (TLS) Protocol Version 1.3

X.509 v3, ISO/IEC 9594-8 (ITU-T Rec. X.509), Information technology – Open Systems

Interconnection – The Directory: Public-key and attribute certificate frameworks

HTTP, Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing


Base64, The Base16, Base32, and Base64 Data Encodings

X690, ISO/IEC 8825-1 (ITU-T Rec. X.690), Information technology – ASN.1 encoding rules: Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules (DER)

X200, ISO/IEC 7498-1 (ITU-T Rec. X.200), Information technology – Open Systems Interconnection – Basic Reference Model: The Basic Model

IEEE 754, 60559-2020 - ISO/IEC/IEEE International Standard - Standard for Floating-Point Arithmetic

HMAC, Keyed-Hashing for Message Authentication

PKCS #1, RSA Cryptography Specifications Version 2.2

PKCS #12, Personal Information Exchange Syntax v1.1

FIPS 180-4, Secure Hash Standard (SHS)

FIPS 197, Advanced Encryption Standard (AES)

UTF-8, UTF-8, a transformation format of ISO 10646

RFC 5280, Internet X.509 Public Key Infrastructure Certificate

and Certificate Revocation List (CRL) Profile

RFC 4514, LDAP: String Representation of Distinguished Names

NTP, Network Time Protocol Version 4: Protocol and Algorithms Specification

RFC 3986, Uniform Resource Identifier (URI): Generic Syntax

RFC 8141, Uniform Resource Names (URNs)

RFC 6455, The WebSocket Protocol

RFC 8259, The JavaScript Object Notation (JSON) Data Interchange Format

RFC 7523, JSON Web Token (JWT) Profile for OAuth 2.0 Client Authentication and

Authorization Grants

RFC 5392, The OAuth 2.0 Authorization Framework

OpenID-Core, OpenID Connect Core 1.0

OpenID-Discovery, OpenID Connect Discovery 1.0

RFC 6960, X.509 Internet Public Key Infrastructure – Online Certificate Status Protocol – OCSP

RFC 5869, HMAC-based Extract-and-Expand Key Derivation Function (HKDF)

RFC 8422, Elliptic Curve Cryptography (ECC) Cipher Suites

RFC 6750, The OAuth 2.0 Authorization Framework: Bearer Token Usage

ISO 8601-1, Date and time - Representations for information interchange - Part 1: Basic rules

RFC 5234, Augmented BNF for Syntax Specifications: ABNF

RFC 4151, The 'tag' URI Scheme

SemVer, Semantic Versioning 2.0.0