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.
In the File menu, select Preferences, expand Digital Signature, and select Time Stamp Servers
If the list of Available servers is empty, or you want to add another timestamp server:
Click New to add a new timestamp server. The Time Stamp Server dialog appears.
Enter the name and URL of a timestamp server, and optional login information
Click OK to save your settings
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.
Click OK
| TIP: If your default timestamp server is unavailable, Nitro Pro 7 uses the first available timestamp server on your list. You are advised to list them in order of preference. |
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.