ISO/IEC 16512-2:2016规定了中继多播协议第2部分（RMCP-2），这是一种应用层协议，用于构建多播树，以便通过基于IP的网络将数据从一个发送方传送到多个接收方，其中IP多播未完全部署。RMCP-2定义了单工组应用在基于IP的网络上的中继多播数据传输能力。 本建议|国际标准规定了以下内容: a） RMCP-2的实体、控制和数据交付模型说明； b） 描述多播代理（MAs）的功能和过程，以构建一对多中继数据路径，并为单工通信中继数据； c） 基本RMCP-2的安全特性说明；和 d） 基本RMCP-2和安全RMCP-2的消息和参数定义。 附录A定义了用于安全RMCP-2的成员身份验证程序。附录B提供了在使用多条SMs时，会话管理器（SMs）之间共享信息的方法。 附录C-G提供了与RMCP-2相关的信息材料。附录H包含一份参考书目。

ISO/IEC 16512-2:2016 specifies the relayed multicast protocol part 2 (RMCP-2), an application？layer protocol that constructs a multicast tree for data delivery from one sender to multiple receivers over an IP-based network, where IP multicast is not fully deployed. RMCP-2 defines relayed multicast data transport capabilities over IP？based networks for simplex group applications. This Recommendation | International Standard specifies the following: a) descriptions of the entities, control and data delivery models of RMCP-2; b) description of the functions and procedures of multicast agents (MAs) to construct a one-to-many relayed data path and to relay data for simplex communication; c) description of the security features of the basic RMCP-2; and d) definitions of messages and parameters of the basic RMCP-2 and secure RMCP-2. Annex A defines a membership authentication procedure for use with the secure RMCP-2. Annex B provides a method for sharing information among session managers (SMs) when multiple SMs are used. Annexes C？G provide informative material related to RMCP-2. Annex H contains an informative bibliography.