You can add a comment and time stamp to a digital signature.
Servers are used to obtain the current time when adding a time stamp to a digital signature. When you send drawing files over the Internet or work on collaborative projects, you can use a specific server to create an accurate, consistent time stamp.
Several government operations (such as the National Institute of Standards and Technology, or the US Naval Observatory) and public systems (such as California Institute of Technology) offer accurate time values. You can also use your own server to create a time stamp by modifying the timesrvr.txt file or creating a custom text file that contains the servers you want to use when adding a time stamp to a digital signature.
The timesrvr.txt file is located in the program’s install directory. By default the install directory for the program is located at \Program Files\AutoCAD 2010. To add a new server, open the timesrvr.txt file with a text editor like Notepad and add the required information for the server. The information that you need to add to the timesrvr.txt file when you want to added your own server is a description and the name of the server. The description that is provided is the value that appears in the drop-down and the name of the server is the URL (Uniform Resource Locator) to the server. The information for each server listed in the timesrvr.txt file must be in the following format:
Description (server_name)
For example:
National Institute of Standards and Technology (time.nist.gov)
To use a file different from the timesrvr.txt file that contains the available time servers to use when creating a time stamp for a digital signature, change the setting of the ADSKSIGTIMESRVR environment variable. For example, change the variable to c:\temp\mytimelist.txt