Firewall Fundamentals

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Firewall Fundamentals

• By Omid Hashemizadegan

Wide Area Computer Networks LLC No.504 Green
Corner BLDG Al Riqqa Road Dubai UAE Tel
00971 4 2211017
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Introduction

• Firewalls are a staple component of secure
  network in todays Internet
• The target Audience are network administrators ,
  Home users and corporate employees
• Basic knowledge about firewall and how it works

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Agenda

• What is a Firewall?
• What can firewall do?

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Overview

• Manage and control network Traffic
• Authenticate Access
• Act as an intermediary
• Protect resources
• Record and report on event

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Firewalls Manage and control Network traffic

• Source IP address
• Source Port
• Destination IP Address
• Destination Port
• IP Protocol
• Packet Header Information (sequence numbers,
  checksums, data flags, payload information, and
  so on)

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• If you know the enemy and know yourself, you
  need not fear the results of hundred battles. If
  you know yourself but not the enemy, for every
  victory gained you will also suffer a defeat. If
  you know neither the enemy nor yourself, you will
  succumb in every battle
• From Sun Tzus The Art of War.

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What are the Threats?

• Targeted versus untargeted attacks
• Viruses, worms and Trojans
• Malicious Content and Malware
• Denial-of service (DoS) attacks
• Zombies
• Compromise of personal information and spyware
• Social engineering
• New attack vectors
• Insecure/poorly designed applications

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What are the motives?

• Effort to gain some financial or monetary gain
• Desire to cause mischief and wreak havoc
• Convincing that they are smarter than you
• Multiple motives

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Determining if you need a firewall

• The cost of restoring or operating the data
• Cost of lost work and downtime
• Cost of less revenue
• Request feedback of training session

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• It is always difficult to get money for
  security before an event occurs.But after an
  event dose, the pocketbooks open right up to
  prevent a recurrence!