Page 141 - DCAP309_INFORMATION_SECURITY_AND_PRIVACY

Unit 9: Firewalls

 Hardware firewalls are precisely what the name entails; a hardware device that is positioned Notes
anywhere in the traffic flow of an organization’s network.

9.9 Keywords

Application Gateway: It is an application program that runs on a firewall system between two
networks.
Firewall: It is a dedicated appliance, or software running on another computer, which inspects
network traffic passing through it, and denies or permits passage based on a set of rules.
Macro: To simplify complicated procedures, many applications allow you to create a script of
commands that the application can run; this script is known as a macro.

Stateful Inspection: It is a newer method that doesn’t examine the contents of each packet but
instead compares certain key parts of the packet to a database of trusted information.
Virus: A virus is a small program that can copy itself to other computers.

9.10 Review Questions

1. How firewalls control the in and out flowing traffic of the network?
2. What is firewall? How can firewall be implemented?
3. Explain the methods that unscrupulous people use to access or abuse unprotected
computers.
4. How firewall controls the traffic flowing in and out of the network?
5. What is proxy server? Explain the function of firewall proxy server.

6. Explain the various characteristics of packet filtering firewall.
7. Make distinction between application level gateway and hardware level gateway.
8. Describe different types of firewall.
9. Write short note on application gateway.
10. Explain the concept of Demilitarized Zone (DMZ) configuration.

Answers: Self Assessment

1. firewall 2. unauthorized
3. virus 4. Demilitarized Zone (DMZ)
5. proxy servers 6. application
7. four-party 8. packet

9. Packet filtering 10. screening router
11. private 12. application gateway
13. destination 14. Hardware
15. Performance

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