本建议|国际标准规定了通过MHS路由消息的方式，以及 补充ITU-T Rec.X.411 | ISO/IEC 10021-4第14.3节中定义的程序。 其他建议| ISO/IEC 10021的部分定义了MHS的其他方面。ITU-T Rec.F.400/X.400 | ISO/IEC 10021-1定义了MHS提供的面向用户的服务。ITU-T Rec.X.402 | ISO/IEC 10021-2提供了 MHS的架构概述。ITU-T Rec.X.411 | ISO/IEC 10021-4定义了消息的抽象服务 传输系统。

This Recommendation | International Standard specifies the means by which messages are routed through the MHS, and supplements the procedures defined in 14.3 of ITU-T Rec. X.411 | ISO/IEC 10021-4. Other Recommendations | parts of ISO/IEC 10021 define other aspects of the MHS. ITU-T Rec. F.400/X.400 | ISO/IEC 10021-1 defines the user-oriented services provided by the MHS. ITU-T Rec. X.402 | ISO/IEC 10021-2 provides an architectural overview of the MHS. ITU-T Rec. X.411 | ISO/IEC 10021-4 defines the abstract-service of the Message Transfer System.