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If supplier Y uses the API to send messages to customer X, only customer X has to enter https://edi4steel.eu. The API will take care of hashing and encryption. Decryption and hash checking still has to be done on customer X side. See example code.
If customer X send back messages through the API to the supplier Y then supplier Y can use the key from https://edi4steel.eu. The API will take care of hashing and encryption. Decryption and hash checking still has to be done on supplier Y side. See example code.
If supplier Z does not use the API to send messages to customer X, supplier Z has to implement the setup process themselves.
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