The actual data messages themselves (normally containing teletype or EDIFACT, though the flows don't care) are transported through the message flows unchanged.
Electronic data Interchange for Administration, Commerce and Transport (EDIFACT) defines which data segments are mandatory or optional, and the number and order of elements.
定义了数据的哪些节是必须的或者是可选的，数据节的数量和数据元素的顺序。
3
This paper probes into the secure message structure in batch UN/ EDIFACT criterion, and presents a security instance message which conforms to the criterion by using the digital signature.