1. DATABASE SECURITY
For CSCL (BIM)

2. Definition Database Security is
the mechanism that protect the database against intentional or accidental threats.
We consider database security in relation to the following situations:
- Theft and Fraud
- Loss of confidentiality

3. Issues
Legal and ethical issues regarding right to access certain information
Private information should be accessed legally by unauthorized party
Public information should be available to everyone
Institutional policies
What kind of information should be make (or should not be) make publicly available
Social networking policies

4. Issues System related issue:
At system level at which various security function should be enforced.
For example at the physical hardware level or at operating system level or the DBMS level

5. DBMS level External level (view level) Conceptual level
Internal level (physical level)

6. DBMS level

7. External level (view level)
External Level is described by a schema i.e. it consists of definition of logical records and relationship in the external view.
It also contains the method of deriving the objects in the external view from the objects in the conceptual view.

8. Conceptual level Conceptual Level represents the entire database.
Conceptual schema describes the records and relationship included in the Conceptual view.
It also contains the method of deriving the objects in the conceptual view from the objects in the internal view.

9. Internal level (physical level)
Internal level indicates how the data will be stored and described the data structures and access method to be used by the database.
It contains the definition of stored record and method of representing the data fields and access aid used.

10. Multiple security level
Identify multiple security level
Categorize the data and user based on
Top Secret
Secret
Confidential
Unclassified

11. Threats
Any intentional or accidental event that may adversely affect the database.
Loss of integrity
Loss of availability
Loss of confidentiality

12. Loss of integrity Should be protected from improper modification
Modification includes creation, insertion, updating, changing status of data and deletion
Integrity lost if unauthorized change are made either intentional or accidental
Result in inaccuracy, fraud and erroneous decisions

13. Loss of availability
Availability refers to making objects available to human user or program to which they have legitimate right

14. Loss of confidentiality
Confidentiality refers protection of data from unauthorized disclosure
Result in loss of public confidence, embarrassment, or legal action against the organization

15. Security Mechanism Discretionary Security Mechanism
Mandatory Security Mechanism
Grant privileges to user
Privileges includes access specific data files, records or fields in a specific mode (such as read, insert, delete or update)

16. Security Mechanism (2) Mandatory Security Mechanism
Enforce multilevel security by classifying the data and users into various security class (level)
Typical security policy is to permit user at certain classification(clearance)
User can access to that classification level or lower level

17. Control Measure
To protect database against threats four find of control measure are used
Access Control
Inference Control
Flow Control
Data Encryption

18. Access Control
Preventing unauthorized person from accessing the system itself
Security Mechanism of DBMS must include provision for restricting access to the database system
Access control is handled by creating user account and password

19. Inference Control
Computer security inference control is the attempt to prevent users to infer classified information from rightfully accessible chunks of information with lower classification. 
Used in statistical database

20. Flow Control
Another security issue is that of flow control, which prevents information from flowing in such a way that it reaches unauthorized users.
Suitable for database over multiuser system or network

21. Encryption Data is encoded using some encryption algorithm
Can be used to encrypt data as well as data transaction over network