In proprietary EDI data exchange with partners takes place via direct communication channels. Various types of encryption and identification protocols can be used in this direct communication, such as AS2, OFTP2, FTPS, SFTP, etc. If there are several partners, the unified management of proprietary communication channels is rather costly and ad-hoc; therefore proprietary EDI is rarely used in multi-party connections. Another important issue is that in the case of communication established within a private sphere, conversion has to be solved in the same sphere, which also represents considerable availability requirements and costs.