1. When can I consider my personal data secure?
Chapter X
When can I consider my personal data secure?

2. How Important is this chapter to undestanding how computers work?7

3. How Important is this chapter to understanding how to use a computer?

4. How can I be sure that my files will be available when I need them?
Data in memory is volatile.
Data in storage is non-volatile so it is always available
As long as it isn’t trashed accidentally or deliberately.
So, when using software (Word, etc.) save often.

5. How can I be sure that my files will be available when I need them.
BACK UP IMPORTANT DATA
Often
Specifically what should YOU do with your data.
At least once per semester, back up your entire computer if it is at all convenient.
I use a removable hard disk
They are currently cheap

6. Securing YOUR data (continued)
I back up my “My Documents” folder on a monthly basis, usually burning it to a CD.
My Really important stuff such as this semester’s notes, tests, grades, etc I back up on a weekly basis to two places – another drive on my home network AND a USB flash memory drive
My really, really, really important stuff such as my financial data, I back up every time I use it to a USB flash drive and monthly to a CD.

7. How can I make my data secure?
Secure data is data that is difficult for OTHERS to access.
There are two basic methods of securing data:
Password systems
Encryption

8. Password Systems
Username and Password – Good systems will not tell you which one is wrong if one of them is.
Usernames are often given to you so you have no choice as to what to use.
Most people choose their own passwords.

9. Password Systems (Cont)
Bad things users do:
Easy to guess passwords.
Tell their passwords to friends.
Write their passwords on a paper and leave it near their computer.
Short passwords can be guessed by brute force.

10. Password Systems (Cont)
If the system is not secured, then the password file may be compromised and all passwords will be unsecured.
Some systems (older versions of Windows) had their password files unencrypted.
The system manager has special powers over users, so if a system manager’s account can be cracked all security is lost.

11. How can you make good passwords?
Make it long.
Use both letters and digits, maybe even special symbols
Use upper and lower case.
Example: dsitBtitw5 (dr sidbury is the best teacher in the world 5)
Example: P=2*(L+w)

12. Encryption Ebub jt fodpefe tp uibu ju epfto’u mppl opsnbm.
Data is encoded so that it doesn’t look normal.

13. What else can go wrong internally?
Programs may make duplicate copies of data which aren’t secure and may even be sent to developers.
Erased data is not really erased, unless you take special precautions.

14. What can go wrong externally?
That is, what problems does the use of a network cause?
Keyboard Sniffers
Wire tapping
Trojan Horses
Viruses
Worms

15. Firewalls – What do they do?
A firewall monitors traffic from one system to another one.
The systems may be individual computers or networks.
Most computers which you buy have a built in firewall. You should configure them or you will not be able to use software correctly.

16. Firewalls
Unfortunately there are lots of different firewalls, so I can’t help you with details about them.
But we can look at some of the settings on Zone Alarm Pro, which is what I use.

17. Summary
Data should be safe (not likely to be lost) and secure (hard for someone else to get)
Safety is primarily implemented with backups
Security is implemented with:
Username/Password systems
Encryption
Antivirus
Firewalls

18. Terminology Audit Trail Caesar Cipher Firewall Incremental Backup
Persistent Storage
Personal Identification Number (PIN)
Public Key Encryption
Transactions
Trojan horses
Virus
Worm