Network Security

1. NETWORK
SECURITY

2. OVERVIEW
• What is security?
• Why do we need security?
• Who is vulnerable?
• Types of network
• Threats
• Areas of Security Weakness
• Hackers & methods of attack
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3. OVERVIEW
• Backups, Encryption & Virus protection
• Common security attacks and countermeasures
– Firewalls
– Intrusion Detection Systems
– IP Sec
– Packet Sniffing
– Social Problems
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4. What is “Security”
• Definition says:
– Freedom from risk or danger; something that
gives or assures SAFETY.
– Freedom from doubt, anxiety, or fear;
CONFIDENCE.
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5. What is “Security”
• Security Attack: Any action that compromises
the security of information.
• Security Mechanism: A mechanism that is
designed to detect, prevent, or recover from a
security attack.
• Security Service: A service that enhances the
security of data processing systems and
information transfers. A security service
makes use of one or more security
mechanisms.
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6. Why do we need security?
• Protect vital info while still allowing access
to those who need it
• Provide authentication and access control
for resources
• Guarantee privacy and correct access
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7. Who is vulnerable?
• Govt and defense agencies
• Contractors to various govt agencies
• Financial institutions and banks
• Internet service providers
• Multinational corporations
• ANYONE ON THE NETWORK
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8. Types of Networks
• LAN
• Interconnected Networks
• Heterogeneous Networks
• Campus Metropolitan & WANs
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9. Areas of Weakness
• Easily guessed/leaked passwords
• Poor login settings
• Data with viruses
• Poorly Implemented Firewalls
• Loss of sys having imp data/info
• Honey-trap or compromise
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10. Hackers
• One who seeks and exploits
weaknesses in a sys or network
• An electronic sport
• Use sophisticated tech to break into sys
• Info useful for others
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11. Hacker Motivations
 Money, profit
 Access to addn resources
 Experimentation and desire to learn
 “Gang” mentality
 Psychological needs
 Self-gratification
 Personal vengeance
 Desire to embarrass the tgt
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12. Methods of attack
• Phone attack (preachers)
• Accts & pswd attack
• Viruses & Trojan Horses
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13. Methods of attack
• Phone attack (preachers)
• Accts & pswd attack
• Viruses & Trojan Horses
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14. Common security attacks and their
countermeasures
• Finding a way into the network : FIREWALLS
• Exploiting software bugs, buffer overflows : IDS
• TCP hijacking : IP SEC
• Packet sniffing : ENCRYPTION
• Social problems : EDUCATION
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15. Firewalls
• A gp of components that collectively form a
barrier between two networks.
• A firewall is like a castle with a drawbridge
– Only one point of access into the network
– This can be good or bad
• Solution
– Admin limits access to end hosts by using a
firewall
– Firewall is kept up-to-date by admin
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16. Firewalls
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Insider
Outsider
Firewall
Firewall
Web server, email
server etc

17. Intrusion Detection Sys
• Monitors network or sys activities for
malicious activities or policy violations and
produces reports to mgt stn.
• Used to monitor for “suspicious activity” on
a network
– Can protect against known software exploits
• Uses “intrusion signatures”
– Well known patterns of behaviour
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18. IP Sec
• Internet Protocol Security (IP Sec) is a protocol
suite for securing Internet Protocol (IP) comn by
authenticating and encrypting each IP packet of a
comn session.
• IP Sec also includes protocols for establishing
mutual authentication between agents at the
beginning of the session and negotiation of
cryptographic keys to be used during the session.

19. Packet Sniffing
• A packet sniffer simply captures all of the
packets of data that pass through a given
network interface.
• Typically, it would only capture packets that
were intended for the machine in question.
• However, if placed into random mode, the
packet sniffer is also capable of
capturing ALL packets traversing the network
regardless of destination.
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20. Social Problems
• People/Users can be just as dangerous as
unprotected computer systems
• People can be lied to, manipulated, bribed,
threatened, harmed, tortured, etc. to give
up valuable info
• Most humans will breakdown once they are
at the “harmed” stage, unless they have
been specially trained
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21. Social Problems
• Humans will continue to be tricked into giving out
information they shouldn’t
• Educating them may help a little here, but,
depending on how bad you want the info, there are a
lot of bad things you can do to get it
• Implement a wide variety of solutions and more
closely monitor who has access to what network
resources and info
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22. Countermeasures
• Identification & authentication
• Access Cont
• Accountability & auditing
• Accuracy
• Reliabilty
• Data Exchange
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23. Countermeasures
• Identification & authentication
• Access Cont
• Accountability & auditing
• Accuracy
• Reliabilty
• Data Exchange
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24. Backups
• Physical loss of sys
• Sys crash
• Virus attack
• Ensure non-corrupted backup
• Reg backups
• Safety of backups as well
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25. Encryption
• Cryptographic tech/the process of encoding
messages (or info) in such a way that others
(hackers) cannot read it, but that
authorized indl can.
• Data remains pvt even after compromised
• Encryption sys/software is protected &
secure
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26. Virus Protection
• Threat to network
• Contact & spread
• Monitor the telltale signs in network
• Trg of users in handling antivirus
• Re-infect capability
• Ensure backups
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27. Elements of a comprehensive
security program
 Have Good Passwords
 Use Good Antiviral Products
 Use Good Cryptography
 Have Good Firewalls
 Have a Backup System
 Audit and Monitor Systems and Networks
 Have Training and Awareness Programs
 Test Your Security Frequently
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28. Conclusion
• The Internet was not created with security in mind.
• Comn can be altered, examined and exploited.
• There is a growing need to protect private info
crossing the public networks that make up the Internet
infrastructure.
• A network security policy, an auditing procedure, and a
violation response plan must all be in place to deal
with any breach or breakdown of network security
before it occurs.
•

29. Questions IF ANY….