AS2 message processing

The DataPower® Gateway uses the MEIG AS2 proxy handler and a Multi-Protocol Gateway to process the received AS2 message.

The following image shows the processing sequence by the DataPower Gateway.
  1. The DataPower Gateway receives an AS2 message from the external trading partner.
  2. The DataPower Gateway parses the AS2 message header.
  3. The MEIG AS2 proxy handler retrieves the exchange profile from the MEIG server.
  4. The MEIG server responds with the requested exchange profile.
  5. The MEIG AS2 proxy handler processes the MEIG integration response.
  6. Depending on the setting, the MEIG AS2 proxy handler processes the AS2 message in one of the following ways.
    • Decrypts the message and verifies the signature, then passes the original message along with its HTTP headers to the Multi-Protocol Gateway for processing.
    • Decrypts the message and verifies the signature, then passes the message body of the decrypted data with signature removed to the Multi-Protocol Gateway for processing.
  7. The MEIG AS2 proxy handler passes the message to the Multi-Protocol Gateway.
  8. The Multi-Protocol Gateway applies relevant processing policy actions on the message.
  9. The Multi-Protocol Gateway sends the processed message to the MEIG server.
  10. The Multi-Protocol Gateway receives the response from the MEIG server and then processes the server response.
  11. The Multi-Protocol Gateway   sends the processed response to the MEIG AS2 proxy handler.
  12. The MEIG AS2 proxy handler generates visibility events.
  13. The MEIG AS2 proxy handler delivers visibility events to the MEIG visibility event endpoint.
  14. The MEIG AS2 proxy handler sends the response to the external trading partner.
Figure 1. Processing of AS2 messages
The figure is described by the preceding text.

During this process, the DataPower Gateway generates a list of visibility events in XML format to represent the lifecycle of a received transaction and report the transaction status. When a transaction is completed, the visibility events for the transaction are sent to the MEIG visibility event endpoint.

Note:
  • The transaction metadata and message payload are not persisted. The processing of AS2 messaging is stateless.
  • The DataPower Gateway does not generate MDN on behalf of the Multi-Enterprise Integration Gateway server. The Multi-Enterprise Integration Gateway generates and processes MDN.