Submissions can be sent to the FDA Electronic Submissions Gateway (ESG) via a web interface also known as WebTrader or by a gateway to gateway connection known as AS2.  After requesting and completing the required Center compliant test and receiving the user authentication credentials, submissions can be sent to the Gateway and then delivered to the Centers for further processing.  The steps below detail the process of a submission as it moves through the Gateway.

1. Upload WebTrader Submission: First, the WebTrader user must prepare the submission according to the Center guidelines. Second, the WebTrader user logs into the WebTrader website and selects the “Send Document” menu option. Then, the user selects the center, submission type, submission, signing certificate, and signing certificate password.  Next, the WebTrader user selects the "send" button to upload the submission. Then, the WebTrader client application, which is running on the end user’s machine, will create an upload package by signing the submission.  If the submission is a folder, the WebTrader client will create a compressed and zipped package.  The name of the submission will change to FolderName.tar.gz.  Learn how to send a submission.
   
   Transmit AS2 Submission: First, the Industry user must prepare the AS2 submission according to the Center guidelines. Second, the Industry user must sign encrypt, and initiate uploading the submission through the Industry’s AS2. AS2 user must work with their vendor for specific instructions on AS2 submission packaging and transmission. 
    

2. Validate Submission Signature: After the upload is complete, ESG validates the signature to make sure it was signed by valid certificate. ESG assigns a unique identifier to the submission called the CoreID.
   
   Note:  If the user sent a submission with a certificate not associated with their account, they will receive an error message and the submission will not be processed.

3. Deliver Receipt to User: After the signature is validated, a receipt is sent back to user. The receipt is called the Message Delivery Notification (also known as 1st Acknowledgement.) If signature validation is successful, the submission will be processed further.
   
   Note:  If submission validation is unsuccessful, no further processing will be performed on the submission.

4. Unpackage Submission: After the successful signature validation, the submission will be unpackaged and restored to its original submission structure.  ESG creates a file / folder with CoreID name and delivers to the selected Center.  The CoreID will be used as file name for all Acknowledgements.
   
   Note 1:  If the user sent a folder / multi-file with an empty sub-folder, the submission cannot be processed.  At this point the user will receive an Acknowledgement (Ack2), but the Acknowledgement will tell them to resubmit due to a corrupt (tar gz) file.
   
   Note 2:  If the user sent a file without an extension (for example a PDF without “.pdf”) the submission will NOT be processed.  ESG Admins will be notified and they will reach out to the user via email.

5. Generate Acknowledgement 2: If the unpackaging was successful, an Acknowledgement is created.  This acknowledgement is known as Ack2.  Ack2 is generated with a submission time stamp and CoreID. The Ack2 file name will be in CoreID.txt format.
   Note:  If the unpackaging was unsuccessful Ack2 will be generated with an error.  Only successfully unpackaged submissions will be processed further.

6. Deliver Ack2 to User:  The Ack2 is sent back to user. The user can opt-in to receive email notifications for when Acks and Receipts are delivered to their WebTrader Inbox. Users should read the receipt to make sure it contains successful message. The user should use the CoreID as reference for any submission related queries sent to the ESG team. If the Ack2 is a text file, the user will be able to view contents.  Acknowledgements in any other format (e.g., PDF), must be downloaded to view the contents of the file.

7. High Level Technical Validation: The center retrieves submission from ESG and performs a high-level technical validation on the submission. The list of center-specific validation steps, click here.

8. Generate Acknowledgement 3: Some centers generate another Acknowledgement with validation results.  This Acknowledgement is known as Ack3.  Depending on the validation results, the Ack3 will contain language confirming the submission has been successfully processed.  The Ack3 may also contain a Technical Rejection Notification.  The Technical Rejection Notification will state why the submission was unsuccessful.

9. Deliver Ack 3 to User: ESG delivers Ack3 to user. Since Ack3 is a PDF file, the user should download the Ack and use a PDF reader to view the contents.