标准摘要
[中文适用范围]： IEC 62541-4:2025 RLV包含官方的IEC国际标准及其红线版本。红线版本仅提供英文版，便于快速比较官方IEC标准与其前一版之间的所有变更。IEC 62541-4:2025定义了OPC统一架构（OPC UA）服务。这些服务是一组抽象的远程过程调用（RPC），由OPC UA服务器实现，并由OPC UA客户端调用。所有OPC UA客户端与服务器之间的交互均通过这些服务进行。所定义的服务被视作抽象服务，因为本文档中并未定义实现的具体RPC机制。IEC 62541-6规定了一种或多种支持实现的具体映射方式。例如，IEC 62541-6中的一种映射是UA-TCP、UA-SC和UA-Binary。在这种情况下，本文档中描述的服务将表现为OPC UA二进制编码的有效载荷，通过OPC UA安全对话进行加密，并通过OPC UA TCP传输。并非所有OPC UA服务器都实现了所有定义的服务。IEC 62541-7定义了规定必须实现哪些服务才能符合特定配置文件的配置文件。附录A中描述了浏览路径名称的BNF（巴科斯-诺尔范式）。本第四版取消并替代了2020年发布的第三版。本版为技术修订版。与前一版相比，本版包括以下重大技术变更：a）向方法调用服务添加新定义，允许方法参数为可选；b）向事件监控项错误场景中添加对SystemStatusChangeEventType的引用；c）增强如何判断证书是否可信的一般描述；d）添加对ECC（椭圆曲线密码）的支持；e）向AggregateFilterResult结构中添加修订后的AggregateConfiguration；f）向BrowseDirection枚举数据类型中添加INVALID；g）向TimestampsToReturn枚举数据类型中添加INVALID；h）添加确保订阅功能在重新传输队列为可选时仍能正常工作的定义；i）添加客户端检查，使其与服务器证书检查对称；j）明确说明，当服务器从LDS-ME返回证书时，不会将“本地”顶级域名附加到证书中，也不会由客户端进行检查；k）添加对已颁发身份令牌过期行为的定义；l）添加新的状态码Good_PasswordChangeRequired到ActivateSession；m）限制AdditionalInfo仅在调试模式下由服务器使用；n）添加新的状态码Bad_ServerTooBusy；o）添加对必须在GetEndpoints响应中包含服务器证书的情况的定义。 [外文原描述]： IEC 62541-4:2025 RLV contains both the official IEC International Standard and its Redline version. The Redline version is available in English only and provides you with a quick and easy way to compare all the changes between the official IEC Standard and its previous edition. IEC 62541-4:2025 defines the OPC Unified Architecture (OPC UA) Services. The Services defined are the collection of abstract Remote Procedure Calls (RPC) that are implemented by OPC UA Servers and called by OPC UA Clients. All interactions between OPC UA Clients and Servers occur via these Services. The defined Services are considered abstract because no particular RPC mechanism for implementation is defined in this document. IEC 62541‑6 specifies one or more concrete mappings supported for implementation. For example, one mapping in IEC 62541‑6 is to UA-TCP UA-SC UA-Binary. In that case the Services described in this document appear as OPC UA Binary encoded payload, secured with OPC UA Secure Conversation and transported via OPC UA TCP. Not all OPC UA Servers implement all of the defined Services. IEC 62541‑7 defines the Profiles that dictate which Services must be implemented in order to be compliant with a particular Profile. A BNF (Backus-Naur form) for browse path names is described in Annex A. 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 new definitions to Method Call Service to allow optional Method arguments; b)addition of reference to SystemStatusChangeEventType for event monitored item error scenarios; c) enhancement of the general description of how determining if a Certificate is trusted; d) addition of support for ECC; e) addition of revisedAggregateConfiguration to AggregateFilterResult structure; f) addition of INVALID to the BrowseDirection enumeration data type; g) addition of INVALID to the TimestampsToReturn enumeration data type; h) addition of definitions that make sure the subscription functionality works if retransmission queues are optional; i) addition of client checks has been added to be symmetric to the Server Certificate check has been added; j) clarification that ‘local’ top level domain is not appended by server into certificate and not checked by client when returned from LDS-ME; k) addition of a definition for expiration behaviour of IssuedIdentityTokens; l) addition of status code Good_PasswordChangeRequired to ActivateSession; m) restriction of AdditionalInfo to servers in debug mode; n) addition of new status code Bad_ServerTooBusy; o) addition of definition for cases where server certificate must be contained in GetEndpoints response.
英文名称OPC unified architecture - Part 4: Services