One of the greatest benefits to adopting a document management system is the long-term protections it provides. You can easily back up and restore immense volumes of data, making it literally impossible to lose anything permanently, assuming the backup infrastructure is also in place.
PDF/A is an archival format of a PDF file that strips out much of the content that challenges the long-term usability of the document.
By only allowing the most simple iteration of the data, it ensures that it will be readable for future purposes:
- Audio and video content are forbidden.
- All fonts must be embedded and also must be legally embeddable for unlimited, universal rendering. This also applies to the so-called PostScript standard fonts such as Times or Helvetica.
- Colorspaces specified in a device-independent manner.
- Encryption is forbidden.
- Use of standards-based metadata is mandated.
- External content references are forbidden.
- LZW and JPEG2000 image compressions are forbidden in PDF/A-1, but JPEG 2000 compression is allowed in PDF/A-2.
- Transparent objects and layers (Optional Content Groups) are forbidden in PDF/A-1, but they are supported in PDF/A-2.
- Provisions for digital signatures in accordance with the PAdES (PDF Advanced Electronic Signatures) standard are supported in PDF/A-2.
- Embedded files are forbidden in PDF/A-1, but PDF/A-2 offers the possibility to embed PDF/A files, allowing archiving of sets of documents in a single file.