Types of PDF Protection – Which is Best

Let’s face it, when it comes to securing important PDF documents, a private folder in your ‘C’ drive doesn’t cut it.

Business-sensitive documents — such as bank password details, employee data, investors’ information, and powers of attorney —are critical to your business. Needless to say, some of your top management will require access to these documents. So, how do you ensure document security while granting access to the right people?

Here are some of the common, yet reliable ways to keep your PDF documents secure:

Passwords

Passwords help you restrict users from editing, printing, or copying your PDF document. You can set the restrictions, and users will not be able to change them unless they have the password. However, you will not be able to prevent users from saving copies of your PDF as these copies will also have the same set of restrictions as the original PDF. 

There are two types of passwords – document open password and permissions password.

• A document open password is required (by the user) to open the PDF. 
• A permissions password is needed to change permission settings you’ve set. If you secure the PDF with both types of passwords, the users can open it with either password, but they will still require the permission password to change the restriction settings.

Passwords offer basic document protection and are used when there’s no infrastructure for stronger controls.  This is because they can be easily removed. The permissions password, for example, can be removed instantly using freely available password recovery tools.

Encryption

This is the process of encoding a document so that only recipients with access to a secret key or token can open and decrypt (or read) the document. It ensures document security by preventing unauthorized access to documents in transit, at rest, and in storage. While encryption guarantees end-to-end protection – it adds a layer of security that makes it more difficult for unauthorized users to view, change, or share the information – it does not prevent authorized users from changing or sharing the document as they see fit.

So there are two issues with document encryption – First, you must have all the keys of all the people you want to send sensitive information to, and second, when users decrypt the confidential information, they can do whatever they want. This means, encryption is an effective measure to start with, but you’ll need more sophisticated ways to control what can be done with the decrypted information.

Encryption does not control the distribution of controlled documents, but it is essential to support other document security technologies. 

Digital Rights Management (DRM)

Ensuring that only intended recipients can access your documents is only half the battle. The rest of the battle is about controlling how the documents are used, where they are used, and for how long they can be used. This is where DRM will help you to protect your information against unauthorized access, sharing, distribution, and piracy.

DRM uses encryption to prevent document theft or interception and has specific controls in place to enforce granular permissions on your document, such as the number of times it was viewed, the last date of access, on which device and from which location it was last accessed, etc.  With DRM, you can enforce rights on reading, editing, copying, printing, expiry, screen grabbing, distribution as well as location- and device-specific controls. You can set an expiry date or put dynamic watermarks on printed content with system and user information displayed on them.

How to choose the right security measures?

Document security features range from simple measures such as password protection to sophisticated systems like DRM adopted by larger corporations. Your choice of the document security solution you implement will depend on your budget, how sensitive your content is, and the type of restrictions you want. Here are some examples:

• If you wish to allow only certain users to view your documents, the easiest way is to add a password and send it to the intended recipients.  Of course, you need to trust the recipient(s) in that they will not then give the documents and their corresponding passwords to others.
• If you are exchanging PDF documents with a group that you trust, you can encrypt the document and share the secret key.  You will have no control over the documents once they have been opened so users can edit and print them.
• If you want certain people to have specific rights to secure documents, then you need DRM.  This ensures that documents cannot be misused.

Conclusion

Passwords can be shared and encryption does not allow you to control document used after the information has been decrypted. So, to gain complete control over document access and use as well as the distribution of content, you need to implement DRM. DRM provides you with the ability to revoke access rights if you suspect that the information has been leaked. You can lock down the document so that it is not distributed to others, at least not without your control.