IEC 62541-6 Ed. 4.0 en:2025

OPC unified architecture - Part 6: Mappings

IEC 62541-6:2025 specifies the mapping between the security model described in IEC 62541 2, the abstract service definitions specified in IEC 62541 4, the data structures defined in IEC 62541 5 and the physical network protocols that can be used to implement the OPC UA specification.
 This fourth edition cancels and replaces the third edition published in 2020. This edition constitutes a technical revision.
 This edition includes the following significant technical changes with respect to the previous edition:
 a) addition of support for ECC to UA Secure Conversation;
 b) use of the AuthorityKeyIdentifier extension in Certificate Revocation Lists;
 c) enhancement of JSON mapping of Unions;
 d) addition of Decimal data type encoding.
 e) description of ECC keyUsage rules;
 f) addition of Media assigned by IANA to UANodeSet definition;
 g) addition of requirements for user and issuer Certificates;
 h) addition of rules which specify what happens when DateTime precision is lost;
 i) addition of rules to allow for the truncation of strings containing embedded nulls.
 J) definition of a normative string representation for NodeId, ExpandedNodeId and QualifiedName for JSON mapping.
 k) requirement that TAI times be converted to UTC;
 l) new possibility to omit Symbol if unknown in JSON encoding;
 m) addition of fields needed to support RolePermissions to the UANodeSet