ISO/IEC 23001-3:2008规定了XML IPMP消息，它是ISO/IEC 21000-4中定义的IPMP信息描述符的简单而自然的扩展。它们允许将与从相关数字项检索的受保护内容元素相关的IPMP信息分派给负责执行访问受保护内容元素所需的IPMP操作的模块。此外，XML IPMP消息提供了一个标准API，允许在负责提供对受保护内容元素（例如音频/视频资源）的访问的模块（IPMP工具）之间交换IPMP信息（例如解密密钥、身份验证信息、许可证等）。 ISO/IEC 23001-3:2008规定的API基于一组XML消息，这些消息定义了设备上不同组件之间或两个设备之间交换的信息格式。 本规范中定义的大多数IPMP消息是ISO/IEC 13818-11和ISO/IEC 14496-13中最初定义的消息从二进制表示形式转换为XML表示形式。为了使ISO/IEC 13818-11和ISO/IEC 14496-13在MPEG-21多媒体框架中协调一致，特别是与ISO/IEC 21000-4协调一致，对其中一些XML消息进行了调整。此外，还定义了许多新的XML消息，以支持扩展的IPMP需求，例如IPMP算法和逻辑之间的分离，使它们能够与设备中的其他组件通信。

ISO/IEC 23001-3:2008 specifies XML IPMP messages which are a simple and natural extension of the IPMP Information Descriptors defined in ISO/IEC 21000-4. They allow dispatching of the IPMP information related to a protected content element retrieved from the associated digital item to the modules in charge of performing the IPMP operations required to access the protected content element. Furthermore, the XML IPMP Messages provide a standard API allowing the exchange of IPMP information (e.g. decryption keys, authentication information, licenses, etc.) between the modules – the IPMP Tools – in charge of providing access to the protected content elements (e.g. audio/visual resources). The API specified by ISO/IEC 23001-3:2008 is based on a set of XML messages defining the format of the information exchanged between the various components on a device, or between two devices. Most of the IPMP Messages defined in this specification are a translation of the messages originally defined in ISO/IEC 13818-11 and ISO/IEC 14496-13 from the binary representation into an XML representation. A number of these XML messages have been adapted in order to harmonise ISO/IEC 13818-11 and ISO/IEC 14496-13 in the MPEG-21 Multimedia Framework and with ISO/IEC 21000-4 specifically. Additionally, a number of new XML messages have been defined to support extended IPMP requirements such as the separation between the IPMP algorithms and the logic enabling them to communicate with the other components in a device.