Financial Transaction Message

ISO8583 message flow

The International Standards Organization (ISO) defines and publishes data standards to be used in exchange the financial messages between acquires and issuers.
ISO8583 ISO standard is commonly used for the banking and financial organization. The ISO8583 messages themselves commonly contain information about what is the type of transaction, where does the transaction come from, Card Number, Amount and Date and Time of transaction etc.

So the layout of ISO8583 messages could be the following.

Custom Header * MTI * Primary Bitmap * Secondary Bitmap

(Optional)

Tertiary Bitmap

(Optional)

Data Element/Data Fields *

* is mandatory.