Technology In ActionHybrid of chapter 7+12: Networking and Security

http://www.sepguy.com

Computer Threats

• Cybercrimes are criminal acts conducted through the use of computers by cybercriminals.

Hackers

• Anyone who unlawfully accesses a computer system

• Types of hackers: – White-hat– Black-hat– Script kiddies

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What Hackers Do

• Steal information from computers:– Credit card numbers– Bank account numbers

• Internet packet sniffing• Commit identity theft

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Denial of Service Attacks

• Backdoor programs – Trojan horse

– Zombies

• Denial of service attacks

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How Hackers Gain Access

• Direct access:– Hacking software

• Indirect access:– Internet connection– Logical ports

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Computer SafeguardsFirewalls

• Software programs or hardware designed to close logical ports to invaders– A firewall is built into Windows XP– More robust firewalls are available

from other vendors.– Firewalls are critical if you have an

always-on broadband connection.

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Network Navigation Devices• Switches and Bridges

– Send data on a specific route through the network

– Bridges send data between collision domains

• Routers– Send information

between two networks

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Network Security Threats

• Human Errors and Mistakes– Accidents and mistakes

• Malicious Human Activity– Current and former employees hacking or

planting viruses

• Natural Events and Disasters– Hurricanes, floods, fire

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Network Security

• Authentication– User ID and password used to access the network– Use of a possessed object for access

• Access privileges– Enable access to certain network systems

• Physical protection measures– Restrict physical access to sensitive network equipment– Magnetic card readers– Biometric access devices

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Network Security• Firewalls

– Prevent access to the network by unauthorized users

– Composed of software and/or hardware– Screen and validate data packets– Bastion host/proxy server

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Network Firewall Layout

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