MPEG-n IPMP system with a wide interoperability is provided. For this purpose, the IPMP_Data_BaseClass is defined, several IPMP data extending from this base class are also defined. IPMP data is the data that describes IPMP information, it includes: IPMP_OpaqueData; IPMP_SelectiveDecryptionMessage; IPMP_AudioWatermarkingInit; IPMP_VideoWatermarkingInit; and IPMP_KeyData. Places where IPMP data extending from IPMP_Data_BaseClass are also specified. With the above work, a IPMP tool from Vendor A will be able to understand the IPMP data constructed by Content Author B, hence the inter-operability will be achieved, that is, the same protected content will be able to be consumed on different vendor's MPEG-n IPMP terminals.