PKI Tutorials - Herong's Tutorial Examples

∟S/MIME and Email Security

∟Digital Signature Scheme for Email Messages

This section describes the digital signature scheme for email messages. The process of signing an email message is the same as signing other digital documents.

To help you understand the digital signature process, I found this diagram from Ghacks.net:

The diagram shows you that:

• The sender must have a private-public pair.
• The sender generates a digital signature the private key and a message digest of the original email.
• The digital signature is attached to the email and delivered to the receiver.
• The receiver decrypts the digital signature using the sender's public key and compares with the message digest of the received email.
• The receiver knows that received email has been tampered with by a third party if the message digest does not match the decrypted digital signature.

Note that the picture above only verifies the integrity of the received document. It does not cover the verification of sender's identity.

Table of Contents

 About This Book

 Introduction of PKI (Public Key Infrastructure)

 Introduction of HTTPS (Hypertext Transfer Protocol Secure)

 Using HTTPS with Google Chrome

 Using HTTPS with Mozilla Firefox

 HTTPS with Microsoft Edge

 Using HTTPS with Apple Safari

 HTTPS with IE (Internet Explorer)

 Android and Server Certificate

 iPhone and Server Certificate

 Windows Certificate Stores and Console

 RDP (Remote Desktop Protocol) and Server Certificate

 macOS Certificate Stores and Keychain Access

 Perl Scripts Communicating with HTTPS Servers

 PHP Scripts Communicating with HTTPS Servers

 Java Programs Communicating with HTTPS Servers

 .NET Programs Communicating with HTTPS Servers

 CAcert.org - Root CA Offering Free Certificates

 PKI CA Administration - Issuing Certificates

 Comodo Free Personal Certificate

 Digital Signature - Microsoft Word

 Digital Signature - OpenOffice.org 3

►S/MIME and Email Security

 What Is S/MIME

►Digital Signature Scheme for Email Messages

 A Simple Email Message Example

 Email Messages with Attachments using MIME

 Email Messages with Digital Signatures using S/MIME

 Encrypted Email Messages using S/MIME

 Digital Signature and Encryption in Outlook

 Email Security Settings in Outlook

 Valid Certificate Required in Outlook

 Message Security Properties in Outlook 2007

 Firefox Extension - Gmail S/MIME

 PKI (Public Key Infrastructure) Terminology

 Archived Tutorials

 References

 Full Version in PDF/EPUB

Digital Signature Scheme for Email Messages - Updated in 2022, by Herong Yang