The Trusted Data Format (TDF) is an open source data protection standard invented by Virtru Co-Founder, Will Ackerly. The TDF is essentially a protective wrapper containing your content. Whether you’re sending an email message, an Excel spreadsheet, or a cat photo, your emails and files are encrypted and “wrapped” in the TDF. When a recipient attempts to open these message and/or files, the TDF wrapper verifies whether that user is eligible to access the data. Once verified, they can decrypt, open, and read the secure content.
For secure files, users may notice that the filename extension has ".tdf" on the end. This lets users know that the file has been encrypted.
There are two file formats that you may encounter with a "tdf.html" file extension:
- A tdf.html file contained within or downloaded from a secure email, and
- A tdf.html file transmitted as an attachment on an unencrypted email or via other file transfer process.
A tdf.html file contained within or downloaded from a secure email has had Persistent File Protection (PFP) applied to it. These files will remain secure when downloaded or shared, requiring that users verify their identity in the Secure Reader before accessing the content.
A tdf.html file transmitted as an attachment on an unencrypted email or via other file transfer process has likely been generated by Virtru's SDKs and is not tied to any email ecosystem. As above, these files will remain secure when downloaded or shared, and require users to verify their identity in the Secure Reader before accessing the content. However, due to differences in the overall architecture, there are some limitations on which browsers can be used to open this type of file. See the list of supported browsers here.
For more detailed information on TDFs and our architecture, visit our Architecture Overview and our Trusted Data Format web page.