A general introduction about the network security and attack types and how we can deal with attacks

1. Ass. Lec Mohanad ALALKAWI
Department of Computer Engineering
4th class

2. General Information
E-Mail web : mohanadalobaidey@gmail.com
Office : 14

3.  Lectures
: - p.m.
 Assignments
 Quizzes
 Midterm exam
 Final exam

4. Outline
 General Definitions
 Introduction to Network Security
 Types of Network security
 Attacks, services and mechanisms
definitions
 Security attacks
 Security services
 Methods of Defense

5. General Definitions
Computer Security
generic name for the collection of tools designed to
protect data and to thwart hackers
Network Security
measures to protect data during their transmission.
Internet Security
measures to protect data during their transmission over a
collection of interconnected networks.

6. Introduction to the Network Security(NS)
Network security (NS) is any activity designed to protect
the usability and integrity of your network and data. It
includes both hardware and software technologies.
Effective network security manages access to the network.
It targets a variety of threats and stops them from
entering or spreading on your network.

7. Types of Network Security
 Access control
Not every user should have access to your network. To keep out
potential attackers, you need to recognize each user and each device.
 Application security
Any software you use to run your business needs to be protected,
whether your IT staff builds it or whether you buy it.
 Email security
Email gateways are the number one threat vector for a security
breach.
 Wireless security
Wireless networks are not as secure as wired ones. Without stringent
security measures, installing a wireless LAN can be like putting
Ethernet ports everywhere, including the parking lot.
 There are many other types you can find in the cisco.

8. Attacks, services and mechanisms
• Need systematic way to define requirements.
• Consider three aspects of information security:
 security attack
 security mechanism
 security service

9. Attacks, Services and Mechanisms definitions
• 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.

10. Security Attack
• Any action that compromises the security of
information owned by an organization
• Information security is about how to prevent
attacks, or failing that, to detect attacks on
information-based systems
• Have a wide range of attacks
• Can focus on generic types of attacks

11. Security Attacks

12. Security Attacks types
• Interruption: This is an attack on availability
• Interception: This is an attack on confidentiality
• Modification: This is an attack on integrity
• Fabrication: This is an attack on authenticity

13. Security Attacks classifying
• Passive attacks
Is the attack that happen when the information moving from
the source to destination.
The information transfer normally from the sender to reviver
but the attack person will be between the sender and receiver
Fig 1.2 will shows the mechanism of Passive attack.
 Active attacks
modification of data stream to:
 masquerade of one entity as some other.
 replay previous messages.
 modify messages
Fig 1.3 show the mechanism of activate attack

14. Passive Attacks
1.Release of Message Contents

15. Passive Attacks
2.Traffic Analysis
Figure 1.2 The mechanism of passive attack

16. Active Attacks
1. Masquerade

17. Active Attacks
2. Replay
Figure 1.3 The mechanism of activate attacks

18. Security Mechanism
 A mechanism that is designed to detect,
prevent, or recover from a security attack.
 No single mechanism that will support all
functions required.
 However one particular element underlies
many of the security mechanisms in use:
cryptographic techniques.

19. Security Service
• Is something that enhances the security of the
data processing systems and the information
transfers of an organization.
• Intended to counter security attacks.
• Make use of one or more security mechanisms to
provide the service.
• Replicate functions normally associated with
physical documents e.g.
 Have signatures or dates.
 Need protection from disclosure, tampering, or
Destruction.

20. Defense methods
 Encryption
 Software Controls (access limitations in a
data base, in operating system protect
each user from other users)
 Hardware Controls (smartcard)
 Policies (frequent changes of passwords)
 Physical Controls