Computer security introduction lecture. Introduction Network Security Basic Components Of Computer Security Online Security Vs Online Safety Risks & Threats Steps to protect information Steps to protect computer Ethical Impact Case study Statistics about Internet Crime survey conclusion

2. Outline :
Introduction
Network Security
Basic Components Of Computer Security
Online Security Vs Online Safety
Risks & Threats
Steps to protect information
Steps to protect computer
Ethical Impact
Case study
Statistics about Internet Crime
survey
conclusion
References

3. Introduction
Computer security is a branch of computer
technology known as information security as
applied to computers and networks.
computer security means the protection of
computing systems and the data that they store
or access
What is Computer Security ?

4. Network Security
Devices, tools, techniques and methodologies
used to secure the network.
The basic component of network security is :
 Firewall .
 Encryption and Decryption : changing plaintext
into ciphertext using key (Encryption). Changing
ciphertext back to plaintext using key
(Decryption).
Two types of encryption : (Symmetric
Encryption, Asymmetric Encryption) .

5. Symmetric Cipher Model

6. Public-Key Cryptography

7. Basic Components of CS
computer security involves providing appropriate
levels of assurance of
– Availability of computing services and data/information
stored in computing systems
– Confidentiality of data/information stored in computing
systems
– Integrity of computing systems and data/information
stored therein

8. Online Security Versus Online Safety
Security: We must
secure our computers
with technology in the
same way that we
secure the doors to
our offices
Safety: We must act
in ways that protect us
against the risks and
threats that come with
Internet use

9. Risks and Threats
To Computer Security are :
Virus
Worm
Trojan Horse
Spyware
Hacking
Phishing
Spoofing
Denial of Service

10. Viruses/Worms
Software programs
designed to invade
your computer, and
copy, damage or
delete your data
Trojan Horses
Viruses that pretend to
be programs that help
you while destroying
your data and damaging
your computer
Spyware
Software that secretly
watches and records
your online activities
or send you endless
pop-up ads

11. Did You Know …
All of these types of attacks are man-made and
intentional.
There is no “natural” or “random” virus.
All of these ride the Internet services you invite in!
Internet services like : ( E-Mail, Peer To Peer
Sharing, Online Gaming, Instant Messaging,
Video and Audio Streaming )

12. Viruses
a program or piece of code that is loaded onto
your computer (without your knowledge and
against your wishes), that (generally) replicates
itself and (generally) delivers a payload.
File Infector Virus : attaches itself to a file on the
computer and is executed when that application is
opened.
( 1972 )

13. Worms
A self-replicating computer program that uses networks to copy
itself to other computers without user intervention.
 infection by passively receiving object that gets itself
executed.
 Stand-alone.
( 1978 )

14. Trojan Horses
Hidden part of some otherwise useful software.
Generally, trojans do not replicate.
Today often on a Web page (Active-X, plugin)
( 1983 )

15. Spyware
Application installed, usually without the user’s knowledge,
intercepting or taking partial control for the author’s personal gain
Estimates as high as 90% of Internet connected computers are
infected with spyware.
Unlike a virus does not self-replicate.

16. Spyware symptoms
Sluggish PC performance
An increase in pop-up ads
Mysterious new toolbars you can’t delete
Unexplained changes to homepage settings
Puzzling search results
Frequent computer crashes

17. How does PC get infected ?
Through CDs, DVDs, Floppy Disk, and Flash Memory
Accepting without reading
Opening e-mail attachments
Not running the latest updates
Pirating software, music, movies
No anti-virus spyware scanner

18. Steps To Protect Information
Practice Internet behavior that lowers your risk
Manage your business information carefully
Use technology to reduce nuisances
Raise the alarm when appropriate

19. Delete Spam without Opening It
Never reply to spam
Technology can help you
identify spam so you can
delete it
Many Internet providers
delete it for you

20. Use Strong Passwords
Keep passwords private and
create ones that are hard
to “crack”
Never share your passwords
with friends or be tricked into
giving them away

21. Turn on an Internet firewall
Keep your operating system up to date
Install and maintain antivirus software
Install and maintain antispyware software
Steps To Protect Computer

22. Turn on an Internet Firewall
An Internet firewall
is like a moat around
a castle, creating a
barrier between
your computer and
the Internet

23. Keep Your System Updated
Install all security
updates as soon as
they are available
Automatic updates
provide the best
protection

24. Install Antivirus Software
Antivirus software can
detect and destroy
computer viruses
before they can cause
damage
Just like flu shots, for
antivirus software to
be effective, you must
keep it up to date
Don’t let it expire

25. Example

26. Install & Maintain Antispyware Software
Use antispyware
software so unknown
people cannot lurk
on your computer
and potentially steal
your information

27. Other Ways to Protect Your PC
- Back up your files regularly
- Practice safe E-mail
- Read website privacy statements
- Close pop-ups using red “X”
- Lock your screen
- Install Spyware Blaster
- Update your Application

28. Back Up Your Files
Save to CD
or DVD
Use a Web-based
backup service

29. Practice Safe E-Mail
Don’t open e-mail attachments unless you
know what they contain and who sent them
Attachment ends with a .exe, .com, .bat,
do not open the attachment unless you
know for a fact that it is clean.
Don’t open, forward, or reply to suspicious
e-mails
Delete spam

30. Close Pop-ups Using Red “X”
Always use the red
“X” in the corner of
a pop-up screen
Never click “yes,”
“accept” or even
“cancel”, because it
could be a trick that
installs software on
your PC

31. Install Spyware Blaster
Spyware Blaster will added a large list of
programs and sites into your Internet
Explorer settings that will protect you from
running and downloading known malicious
programs.

32. Lock Your Screen
Locking your laptop
or workstation while
away from it is good
security sense.
Use a password to start
up or wake-up your
computer.

33. Update Your Application
It is also possible for other programs on your computer
to have security vulnerability that can allow malware to
infect you. Therefore, it is also a good idea to check for
the latest versions of commonly installed applications
that are regularly patched to fix vulnerabilities.

34. Ethical Impact
Question: should schools offer a
course that teaches students how to
hack systems, why?
Violating intellectual property : By
 Software piracy (cracking).
 Hacking others’ devices and stolen their effort .
Computer security reduce this
violating.

35. Ethical Impact(cont)
Many people used a cracked SW and
claim that they want to test it before
they buy it (is that true , why ?)
Other people said : why we have to pay
money while these cracked SW is free?
( is that true , why ?)

36. Ethical Impact(cont)
Violating privacy : hacking other
computers will violate the privacy and
making hacker see what he is not
suppose to see .

37. Case Study (1) : About Phishing
example of a phishing published in the Washington Post (2004 ). Story of
William Jackson from Katy, Texas. Jackson received e-mail from what
appeared to be ( PayPal ) payment offices.
The e-mail warned him that his account would be suspended until he
updated it with financial information. The e-mail provided a link for Jackson
to the website where he could update his information. He entered in credit
card numbers, bank numbers, social security numbers and other personal
identification information.
The website ended up being fraudulent and Jackson lost several hundred
dollars. William Jackson could have lost much more money as a result of the
Phishing website he had entered.

38. Case Study (2) : About Spyware
In March ( 2005 ), British police foiled a plot to steal £220
million from ( Sumitomo Mitsui Bank ) in London.
Cybercriminals had compromised the bank’s computer
systems and secretly deployed a keylogger program that
was perhaps part of a Trojan horse. The spyware relayed
password and access information to the criminals, who
intended to transfer the funds electronically. A man in Israel
was arrested after allegedly trying to transfer £13.9 million
into an Israeli account.

39. Statistics about Internet Crime
This statistic is done in USA, that include many types of crime,
such as auction fraud, spam, credit card fraud and so on.

40. Survey

41. Survey(cont)

42. Survey(cont)

43. Survey(cont)

44. Conclusion
Now that you have completed this web quest on
Computer Security you are now aware of the
possible security treats to computer systems. Not
only that, but you are now better able to protect
your computers as well as recommend security
measures to others

45. References
http://en.wikipedia.org/wiki/Computer_security
http://www.clearwisdom.net/emh/articles/2008/7/23/99177.html
http://its.ucsc.edu/security_awareness/intro.pdf
http://nurseweb.ucsf.edu/public/07fa-computer-security.ppt
http://www.acsac.org/secshelf/book001/02.pdf

46. Thank You For Listening
Any Question ?