标准摘要
[中文适用范围]： IEC 62541-12:2025 规定了 OPC 统一架构（OPC UA）客户端和服务器在不同场景下与发现服务器（DiscoveryServer）进行交互的方式。该标准明确了本地发现服务器（LocalDiscoveryServer）、本地发现服务器-ME（LocalDiscoveryServer-ME）和全球发现服务器（GlobalDiscoveryServer）的要求。同时，它还定义了证书管理、密钥凭证管理和授权服务的信息模型。附录A介绍了部署和配置方面的信息。附录B定义了节点集（NodeSet）和数字节点ID（NodeIds）。附录F提供了本地发现服务器（LDS）的安装规则。附录H将本文档中定义的证书管理与IETF RFC 7030进行比较。本版标准取代了2020年发布的首版标准，构成了一次技术修订。与前一版相比，本版标准包含了以下重要的技术变更：a）新增了“数量模型”（Quantity Model），可用于工程单位（EngineeringUnit）属性的引用。该模型定义了量和相应的单位，并提供了替代单位及其转换方式；b）新增了关于“值精度”（ValuePrecision）属性的规则：• 也可用于其他子类型，如持续时间（Duration）和小数（Decimal）；• 当“值精度”为负值时，增加了额外的规则。 [外文原描述]： IEC 62541-12:2025 specifies how OPC Unified Architecture (OPC UA) Clients and Servers interact with DiscoveryServers when used in different scenarios. It specifies the requirements for the LocalDiscoveryServer, LocalDiscoveryServer-ME and GlobalDiscoveryServer. It also defines information models for Certificate management, KeyCredential management and AuthorizationServices. Annex A informatively discusses deployment and configuration aspects. Annex B defines NodeSet and numeric NodeIds. Annex F provides installation rules for the LDS. Annex H compares the Certificate management defined in this document with IETF RFC 7030. This second edition cancels and replaces the first 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 a "Quantity Model" which can be referenced from EngineeringUnit Properties. The model defines quantities and assigned units. In addition it provides alternative units and the conversion to them; b) addition of rules for ValuePrecision Property: • can also be used for other subtypes like Duration and Decimal. • additional rules when ValuePrecision has negative values.
英文名称OPC unified architecture - Part 12: Discovery and global services