AR Invoice encryption issue.

Summary

Client need Receivable Invoice to be encrypted while delivering to the customer .

Content

Hi Experts,

Now I am working for  Health care project and the AR invoice generated are having patient information , which they want to encrypt. In the current system manually they are opening the AR invoice and from the view image  they are downloading and after  encryption they are sending to the respective customers manually.

Oracle suggested the SFTP server where each customer can login and see the invoice ,but client is not agree for the same as this is not secure any one having the SFTP access  will be able to see each others invoice and now they have to create lot of credentials for all the customers for whom they are sending invoice . They are also not agreeing with the secure password concept.