
Appendix A
Gathering Information From the E-mail Header
When an e-mail message is sent, it goes from the sender’s system to a
mail server program, also known as a message transfer agent. The mail
server program receives the message from the sender’s message user
agent, which is the name given to the software that allows the user to
access and manage e-mail (e.g., Microsoft Outlook, Lotus Notes,
Eudora). The mail server program (e.g., Microsoft Exchange Server,
UNIX sendmail), puts its Internet Protocol (IP) address and the cur-
rent date and time in a Received header at the top of the e-mail mes-
sage. It then passes the message to the next mail ser