Securing Your Desktop ComputerModule 11 – Preventing unwanted Internet content

Thomas Erickson ThomasCISSP@gmail.com

CISSP and Certified Ethical Hacker

Purpose, Process and Payoff

•Purpose: The purpose of this module is understanding the importance of content filtering and a method to implement content filtering at home and/or work.

•Process: Our process will be to discuss, teach and demonstrate foundational DNS principles and the importance of content filtering

Payoff: Being able to state why content filtering is needed and how to implement a free content filtering system at home or work.

Purpose, Process and Payoff

Module 11 – Preventing unwanted Internet content

Objectives

• By the end this module, you will be able to• State the basic components of DNS• Describe the importance of content filtering • Be able to implement a content filtering solution for

application at home and or work.

Module 11 – Preventing unwanted Internet content

Understanding DNS

• Domain Name Service (DNS) maps Internet Protocol (IP) addresses to a human understandable name like cnn.com.

• A user types in cnn.com and DNS translates the name to an IP address ( Ex: 208.67.219.130)

• cnn.com is much easier for humans to remember

Why is content filtering needed?

• Legal liability! If for example a “unsafe work environment” is perceived by an employee and they submit a sexual harassment claim because they saw objectionable content on another employees' computer (web or screen saver).

• Preventing destructive behaviour cultivation at the workplace

• Worker productivity• Sensitive information leak to

social networking/blogs etc• Often users will click on

email they think is legitimate and enter bank account information from phising attempts

• Others?

Free solutions to Content filtering

• “OpenDNS gives you the option to block dozens of categories on your networks, for free. From social networking to job sites, from gambling to video sharing, from webmail to alcohol and more: with OpenDNS, you make the choice about what's available on your network (OpenDNS.com).”

Example:

Demonstration -- setup of OpenDNS

Simply point your workstations to OpenDNS'

DNS servers

OR point your router to OpenDNS' DNS servers

• What are the advantages of using your router instead of your workstation's DNS settings?

• Advantages of creating a free account with OpenDNS include control over categories, stats, whitelisting domains, etc.

Demonstration

Evaluation Review

• What are the basic components of DNS?• What happens when a user attempts to access a “denied”

website?

• How do you configure your workstation to utilize OpenDNS?

• Why is content filtering important?

• Questions?

• We have learned that OpenDNS can solve content filtering challenges easily and inexpensively!

Purpose, Process and Payoff

•Purpose: The purpose of this module is understand the importance of content filtering and a method to implement content filtering at home and/or work.

OUTCOME: You are now familiar with OpenDNS' free content filtering and can successfully implement a free content filtering system at home/work.•Process: Show, teach and discuss foundational DNS principles and the importance of content filtering

OUTCOME: We solidified learning by Q&A, discussion and post lecture lab exercise •Payoff: State why content filtering is needed and implement a free content filtering system at home or work.

OUTCOME: You can now benefit from Internet content filtering to decrease your exposure to harmful content and Phising attempts

Summary-recap of keytake-aways

Purpose, Process and Payoff

•Purpose: The purpose of this module is understand the importance of content filtering and a method to implement content filtering at home and/or work.

OUTCOME: You are now familiar with OpenDNS' free content filtering and can successfully implement a free content filtering system at home/work.•Process: Show, teach and discuss foundational DNS principles and the importance of content filtering

OUTCOME: We solidified learning by Q&A, discussion and post lecture lab exercise •Payoff: State why content filtering is needed and implement a free content filtering system at home or work.

OUTCOME: You can now benefit from Internet content filtering to decrease your exposure to harmful content and Phising attempts

Summary-recap of keytake-aways

Purpose, Process and Payoff

•Purpose: The purpose of this module is understand the importance of content filtering and a method to implement content filtering at home and/or work.

OUTCOME: You are now familiar with OpenDNS' free content filtering and can successfully implement a free content filtering system at home/work.•Process: Show, teach and discuss foundational DNS principles and the importance of content filtering

OUTCOME: We solidified learning by Q&A, discussion and post lecture lab exercise •Payoff: State why content filtering is needed and implement a free content filtering system at home or work.

OUTCOME: You can now benefit from Internet content filtering to decrease your exposure to harmful content and Phising attempts

Summary-recap of keytake-aways

Reflecting

• What was the most valuable thing you learned?• What newly learned principle will you use in the near-term at your home/work-place?

Next module after lab and break

• Lab Exercise 11.1 – Configuring your workstation to use OpenDNS – follow handout.

• NEXT: Module 12 – Using Thunderbird and Gpg to encrypt email text

• Break (10 minutes) – Bathrooms are down the hall to the right, fluids and refreshments can be found in the lobby.