Digital signatures provide an electronic means of verifying the authenticity of signatures that are attached to drawing files.
When you receive a file that contains a digital signature, you can check whether the file was modified since it was signed, and other information.
When you receive a file that contains a digital signature from a certificate authority that is not recognized by your operating system, you may need to obtain the root certificate (the highest level of certificate in a certificate chain) before you can determine if the digital ID in the digital signature is valid.