Security in PDF(Adobe)

http://www.adobepress.com/articles/article.asp?p=1272495

======Digist (Certify)

Certifying PDF Files

Earlier in this exercise, you signed a PDF document to signify that you had approved the content and requested changes. You can also certify the contents of a PDF document. Certifying a document rather than signing it is useful if you want the user to be able to make approved changes to a document. When you certify a document and a user makes approved changes, the certification is still valid. You can certify forms, for example, to guarantee that the content is valid when the user receives the form. You, as the creator of the form, can specify what tasks the user can perform. For example, you can specify that readers can fill in the form fields without invalidating the document. However, if a user tries to add or remove a form field or a page, the certification will be invalidated.

TIP

Before you distribute a document that you intend others to sign or fill in, you should enable usage rights for Adobe Reader users (choose Advanced > Extend Features in Adobe Reader).

Now you'll certify a form to be sent to clients of a winery, asking them to estimate their purchases. By certifying the form, you are sure that the client uses the form as you designed it, with no additions or deletions to the form fields.

1. Choose File > Open, and open the Final_Survey.pdf file in the Lesson08 folder.
2. Choose File > Properties, and click the Security tab.

   The information in the Document Properties dialog box shows that no security and no restrictions have been applied to the document.

3. Click Cancel to close the Document Properties dialog box without making any changes.
4. Choose Advanced > Sign & Certify > Certify with Visible Signature.
5. Click Drag New Signature Rectangle. Click OK, and click OK again.

   You'll use the digital ID that you created earlier in the exercise to certify the file.

6. Drag anywhere in the document to create a signature field. We created a signature field at upper right, next to the logo. Then click the Sign Document button on the document message bar.
7. In the Certify Document dialog box, if you have created more than one digital ID, select the digital ID to use. We selected T. Simpson, Director.
8. Enter your password. We entered Lotion123.
9. For Appearance, select Logo.
10. Choose a reason for signing the document. We chose to certify that we attested to the accuracy and integrity of the document.
11. From the Permitted Actions After Certifying menu, choose "Annotations, form fill-in, and digital signatures."
12. Click Sign to complete the certification process (see Figure 20).
    

    Figure 20

13. Save your file as Final_Survey_Cert.pdf.
14. Click the Signatures button to open the Signatures panel and review which actions the certification allows. You may need to expand the entries in the panel (see Figure 21).
    

    Figure 21

15. When you're finished reviewing the certification information, click the Close button to close the Signatures panel.

TIP

Whenever you open a certified document, you'll see a Certification icon at the left of the message bar. You can click this icon at any time to see certification information for the document.