Adobe acrobat 7.0.5 sdk User Manual

Providing Document Security

You can apply permissions to a PDF document, but some applications may not respect 
these permissions. In these cases, it is desirable to be able to detect unauthorized changes 
to the document. 

The author signature for a document makes Modification, Detection, and Prevention (MDP) 
possible. When this type of signature is applied, it is possible to certify the document, 
which means that you specify information about its contents and the types of changes that 
are allowed in order for the document to remain certified.

You certify the document by applying an author signature to it. If necessary, you can create 
an author signature field using Acrobat JavaScript and then sign it as described in 

When you validate a signature, you verify the signer’s identity and assess any changes 
made after the document was signed. For an identity to be valid, the signer’s certificate, or 
one of its parent certificates that was used to issue the signer’s certificate, must be in your 
list of trusted identities, and it must not have expired or been revoked.

Using the Acrobat SDK, you can validate a signature from a plug-in, from Acrobat 
JavaScript, or from and external application using IAC.

In Adobe Acrobat 7.0, you can save security settings as policies that you can reuse. Security 
policies include the type of security encryption, the permission settings, and information 
about who can open the document or change security settings. There are two kinds of 
security policies:

●

A user policy is developed and applied by an individual user. If you apply the same 
security settings to various documents, you can save time by creating a user policy and 
then reapplying the user policy to documents without having to specify the security 
settings each time. User policies for passwords and public key certificates are stored on 
your local computer. If you have access to Adobe Policy Server, you can also create a user 
policy that is stored on a policy server and is available only to the person who creates it.

●

An organizational policy is created by an Adobe LiveCycle Policy Server administrator 
and is stored on a policy server to be shared by a group of users. Adobe Policy Server 
controls access to PDF documents and auditing events as defined by the security policy. 
You can use Adobe LiveCycle Policy Server only if your company has purchased rights 
and made it available to you.