1. Internet Services and Email
Chapter 15
Internet Services and

2. FIGURE 15.0.F01: Elements of email format.

3. FIGURE 15.0.F02: Email in a rich text format.
Courtesy of Dr. Richard Smith

4. FIGURE 15.0.F03: Email text with MIME formatting.

5. TABLE 15.0.T01: Port numbers for email protocols

6. FIGURE 15.0.F04: Tracking an email’s journey.

7. FIGURE 15.0.F05: Following the email in Figure 15.4.

8. FIGURE 15.0.F06: Is this really an email from the president of the United States?
Used with permission from Microsoft

9. FIGURE 15.0.F07: Headers from the “presidential” email.

10. FIGURE 15.0.F08: Excerpt from a signed email message.

11. FIGURE 15.0.F09: A window from a 2003 phishing attack.
Courtesy of Dr. Richard Smith

12. TABLE 15.0.T02: A simple policy for managing an Internet connection

13. FIGURE 15.0.F10: Traffic controls involve different packet headers.

14. FIGURE 15.0.F11: Packet filtering examines individual packet fields.

15. FIGURE 15.0.F12: Session filtering keeps state across packets.

16. FIGURE 15.0.F13: Application filtering applies to multiple packets.

17. TABLE 15.0.T03: Format of simple firewall rules

18. TABLE 15.0.T04: Firewall controls to enforce Amalgamated’s Internet policy

19. FIGURE 15.0.F14: Single-firewall topology with an external bastion host.

20. FIGURE 15.0.F15: Three-legged firewall with a DMZ.

21. FIGURE 15.0.F16: Dual-firewall topology with a DMZ.