However, the problem you have with FTPS and SFTP is although the files are securely transferred to your server, once they're uploaded, anyone who accesses the server can see them, because they aren't encrypted. With this in mind, I prefer your first solution, which is to have your hosts encrypt the files using the recipients public PGP key. This option not only ensures the files are encrypted while in transit, and when at rest, but...
also only the intended recipient can decrypt and view the files. The best solution to your problem, however, is probably a combination of both PGP-encrypted files and a secure FTP connection. Because even if your PGP encrypted files are secure, if your hosts use plain FTP to upload files to your server the username and password used to access the server are sent in the clear. An attacker could potentially steal this information and use it to gain access to the FTP server and upload malicious files or delete existing files.
Related Q&A from Michael Cobb
The increasing popularity of bug bounty programs leaves many wondering if they can improve enterprise software security. Expert Michael Cobb ...continue reading
Expert Michael Cobb explains how password change frequency and reuse for third-party apps should be addressed in enterprise password policies.continue reading
Learn how a Web-based free spam-filtering service can secure email and prevent spam from attacking your enterprise.continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.