Digital signature timestamp

Digital timestamps mark a PDF signature with the time and date as proof of integrity. A timestamp shows that the contents of the document existed at a point in time, and are unchanged.

For added security, digital signatures can include a timestamp from an independent, trusted authority. Nitro Pro 7 is able to utilize a timestamp server to help ensure that the timestamp is precise and secure, since the system clock could be modified by a user.

To manage digital timestamp settings:

1. In the File menu, select Preferences, expand Digital Signature, and select Time Stamp Servers

2. If the list of Available servers is empty, or you want to add another timestamp server:

   1. Click New to add a new timestamp server. The Time Stamp Server dialog appears.

   2. Enter the name and URL of a timestamp server, and optional login information

   3. Click OK to save your settings

3. To manage existing settings for a timestamp server, tick the Acquire timestamp from attestable server checkbox, select a timestamp server from the list of Available servers, and then do any of the following:

   • To update properties for the selected timestamp server, click Edit, and enter new information on the Time Stamp Server dialog

   • To remove the selected timestamp server, click Delete

   • To use a specified timestamp server by default for every timestamp, click Set Default. A star marks the default timestamp server.

4. Click OK

When you look at the properties of a digital signature, time validity is shown as one of the following:

• Signature date/time are from the clock on the signer’s computer

• Signature is timestamped but the timestamp could not be verified

• Signature is timestamped

For more information, see Digital signatures.

Digital signature timestamp