Introduction

If you tried to link to the internet without a firewall, your computer will be disabled and then you may need many days to recover it. If you work in organization that care of customers or in sales department for example, you should keep and protect their information from penetration from outsiders. Outsiders may destroy valuable and confidential data of customers and that result in disabling your business to operate.
In business today, organizations need to have security and control a top priority. Security means the policies, procedures, and technical measures that used to prevent unauthorized access, alteration, or physical damage to information system. Controls are methods, policies, and organizational procedures that ensure the safety of the organization's assets; the accuracy and reliability of its records; and operational adherence to management standards.