Microsoft Office Tutorials and References
In Depth Information
Topic C: Sharing and securing documents
A digital signature is an electronic security stamp that is used to authenticate a form,
macro, or document. The signature helps you confirm that the file, macro, or e-mail
message originated from the person who signed it and that no one has altered it. To use
a digital signature, you need to obtain and install a digital certificate. A digital
certificate is a file that verifies that a digital signature is valid.
To obtain a digital certificate, you or your organization should submit an application to
a commercial certification authority, such as VeriSign Inc. The application can also be
submitted to your internal security administrator or an information technology (IT)
professional. You can also create your own digital certificates, called self-signed
projects , by using the Selfcert.exe tool. However, self-signed projects might be
considered unauthenticated and might generate a warning because they aren’t
sanctioned by any certification authority.
When you receive a digital certificate, you also receive instructions on how to install it
on your computer. After installing the certificate, you can use it as a digital signature to
sign a file. After a document is signed digitally, it becomes read-only. This prevents
modifications and preserves the integrity of the document.
C-4: Discussing digital signatures
Questions and answers
1 What is a digital signature?
2 Why would you use a digital signature?
3 What is a digital certificate?
4 What is the risk of creating your own digital certificate?
5 True or false? After a document is digitally signed, it becomes read-only.