1. Data and Applications Security Developments and Directions Dr. Bhavani Thuraisingham The University of Texas at Dallas Lecture #4 Supporting Technologies January 2010

2. Objective of the Unit l This unit will provide an overview of the supporting technologies

3. Outline of Part I: Information Security l Operating Systems Security l Network Security l Designing and Evaluating Systems l Web Security l Other Security Technologies

4. Operating System Security l Access Control - Subjects are Processes and Objects are Files - Subjects have Read/Write Access to Objects - E.g., Process P1 has read acces to File F1 and write access to File F2 l Capabilities - Processes must presses certain Capabilities / Certificates to access certain files to execute certain programs - E.g., Process P1 must have capability C to read file F

5. Mandatory Security l Bell and La Padula Security Policy - Subjects have clearance levels, Objects have sensitivity levels; clearance and sensitivity levels are also called security levels - Unclassified < Confidential < Secret < TopSecret - Compartments are also possible - Compartments and Security levels form a partially ordered lattice l Security Properties - Simple Security Property: Subject has READ access to an object of the subject’s security level dominates that of the objects - Star (*) Property: Subject has WRITE access to an object if the subject’s security level is dominated by that of the objects\

6. Covert Channel Example l Trojan horse at a higher level covertly passes data to a Trojan horse at a lower level l Example: - File Lock/Unlock problem - Processes at Secret and Unclassified levels collude with one another - When the Secret process lock a file and the Unclassified process finds the file locked, a 1 bit is passed covertly - When the Secret process unlocks the file and the Unclassified process finds it unlocked, a 1 bit is passed covertly - Over time the bits could contain sensitive data

7. Network Security l Security across all network layers - E.g., Data Link, Transport, Session, Presentation, Application l Network protocol security - Ver5ification and validation of network protocols l Intrusion detection and prevention - Applying data mining techniques l Encryption and Cryptography l Access control and trust policies l Other Measures - Prevention from denial of service, Secure routing, - - -

8. Data Security: Access Control l Access Control policies were developed initially for file systems - E.g., Read/write policies for files l Access control in databases started with the work in System R and Ingres Projects - Access Control rules were defined for databases, relations, tuples, attributes and elements - SQL and QUEL languages were extended l GRANT and REVOKE Statements l Read access on EMP to User group A Where EMP.Salary Security - Query Modification: l Modify the query according to the access control rules l Retrieve all employee information where salary < 30K and Dept is not Security

9. Steps to Designing a Secure System l Requirements, Informal Policy and model l Formal security policy and model l Security architecture - Identify security critical components; these components must be trusted l Design of the system l Verification and Validation

10. Product Evaluation l Orange Book - Trusted Computer Systems Evaluation Criteria l Classes C1, C2, B1, B2, B3, A1 and beyond - C1 is the lowest level and A1 the highest level of assurance - Formal methods are needed for A1 systems l Interpretations of the Orange book for Networks (Trusted Network Interpretation) and Databases (Trusted Database Interpretation) l Several companion documents - Auditing, Inference and Aggregation, etc. l Many products are now evaluated using the federal Criteria

11. Security Threats to Web/E-commerce

12. Other Security Technologies l Middleware Security l Insider Threat Analysis l Risk Management l Trust and Economics l Biometrics l Secure Voting Machines l - - - - -

13. Outline of Part II: Data Management l Concepts in database systems l Types of database systems l Distributed Data Management l Heterogeneous database integration l Federated data management

14. An Example Database System Adapted from C. J. Date, Addison Wesley, 1990

15. Metadata l Metadata describes the data in the database - Example: Database D consists of a relation EMP with attributes SS#, Name, and Salary l Metadatabase stores the metadata - Could be physically stored with the database l Metadatabase may also store constraints and administrative information l Metadata is also referred to as the schema or data dictionary

16. Functional Architecture User Interface Manager Query Manager Transaction Manager Schema (Data Dictionary) Manager (metadata) Security/ Integrity Manager File Manager Disk Manager Data Management Storage Management

17. DBMS Design Issues l Query Processing - Optimization techniques l Transaction Management - Techniques for concurrency control and recovery l Metadata Management - Techniques for querying and updating the metadatabase l Security/Integrity Maintenance - Techniques for processing integrity constraints and enforcing access control rules l Storage management - Access methods and index strategies for efficient access to the database

18. Types of Database Systems l Relational Database Systems l Object Database Systems l Deductive Database Systems l Other - Real-time, Secure, Parallel, Scientific, Temporal, Wireless, Functional, Entity-Relationship, Sensor/Stream Database Systems, etc.

19. Relational Database: Example Relation S: S# SNAME STATUS CITY S1 Smith 20 London S2 Jones 10 Paris S3 Blake 30 Paris S4 Clark 20 London S5 Adams 30 Athens Relation P: P# PNAME COLOR WEIGHT CITY P1 Nut Red 12 London P2 Bolt Green 17 Paris P3 Screw Blue 17 Rome P4 Screw Red 14 London P5 Cam Blue 12 Paris P6 Cog Red 19 London Relation SP: S# P# QTY S1 P1 300 S1 P2 200 S1 P3 400 S1 P4 200 S1 P5 100 S1 P6 100 S2 P1 300 S2 P2 400 S3 P2 200 S4 P2 200 S4 P4 300 S4 P5 400

20. Example Class Hierarchy Document Class D1 D2 Book Subclass B1 # of Chapters Volume # Print-doc-att(ID) Method1 : Journal Subclass J1 Print-doc (ID) Method2: ID Name Author Publisher

21. Example Composite Object Composite Document Object Section 1 Object Section 2 Object Paragraph 1 Object Paragraph 2 Object

22. Distributed Database System Communication Network Distributed Processor 1 DBMS 1 Data- base 1 Data- base 3 Data- base 2 DBMS 2 DBMS 3 Distributed Processor 2 Distributed Processor 3 Site 1 Site 2 Site 3

23. Data Distribution EMP1 SS#NameSalary 1John20 2Paul30 3James40 4Jill50 60 5Mary 6Jane70 D# 10 20 20 20 10 20 DnameD#MGR 10 30 40 Jane David Peter DEPT1 SITE 1 SITE 2 EMP2 SS#NameSalary 9Mathew 70 D# 50 Dname D#MGR 50 Math John Physics DEPT2 David 80 30 Peter9040 7 8 C. Sci. English French 20 Paul

24. Interoperability of Heterogeneous Database Systems Database System A Database System B Network Database System C (Legacy) Transparent access to heterogeneous databases - both users and application programs; Query, Transaction processing (Relational) (Object- Oriented)

25. Different Data Models Node A Node B Database Relational Model Network Model Node C Database Object- Oriented Model Network Node D Database Hierarchical Model Developments: Tools for interoperability; commercial products Challenges: Global data model

26. Federated Database Management Database System A Database System B Database System C Cooperating database systems yet maintaining some degree of autonomy Federation F1 Federation F2

27. Federated Data and Policy Management Export Data/Policy Component Data/Policy for Agency A Data/Policy for Federation Export Data/Policy Component Data/Policy for Agency C Component Data/Policy for Agency B Export Data/Policy

28. Outline of Part I: Information Management l Information Management Framework l Information Management Overview l Some Information Management Technologies l Knowledge Management

29. What is Information Management? l Information management essentially analyzes the data and makes sense out of the data l Several technologies have to work together for effective information management - Data Warehousing: Extracting relevant data and putting this data into a repository for analysis - Data Mining: Extracting information from the data previously unknown - Multimedia: managing different media including text, images, video and audio - Web: managing the databases and libraries on the web

30. Data Warehouse Oracle DBMS for Employees Sybase DBMS for Projects Informix DBMS for Medical Data Warehouse: Data correlating Employees With Medical Benefits and Projects Could be any DBMS; Usually based on the relational data model Users Query the Warehouse

31. Data Mining Knowledge Mining Knowledge Discovery in Databases Data Archaeology Data Dredging Database Mining Knowledge Extraction Data Pattern Processing Information Harvesting Siftware The process of discovering meaningful new correlations, patterns, and trends by sifting through large amounts of data, often previously unknown, using pattern recognition technologies and statistical and mathematical techniques (Thuraisingham 1998)

32. Multimedia Information Management Video Source Scene Change Detection Speaker Change Detection Silence Detection Commercial Detection Key Frame Selection Story Segmentation Named Entity Tagging Broadcast News Editor (BNE) Broadcast News Navigator (BNN) Video and Metadata Multimedia Database Management System Web-based Search/Browse by Program, Person, Location,... Imagery Audio Closed Caption Text Segregate Video Streams Analyze and Store Video and Metadata Story GIST Theme Frame Classifier Closed Caption Preprocess Correlation Token Detection Broadcast Detection

33. Image Processing: Example: Change Detection: l Trained Neural Network to predict “new” pixel from “old” pixel - Neural Networks good for multidimensional continuous data - Multiple nets gives range of “expected values” l Identified pixels where actual value substantially outside range of expected values - Anomaly if three or more bands (of seven) out of range l Identified groups of anomalous pixels

34. Semantic Web 0 Some Challenges: Security and Privacy cut across all layers XML, XML Schemas Rules/Query Logic, Proof and Trust TRUSTTRUST Other Services RDF, Ontologies URI, UNICODE PRIVACYPRIVACY 0 Adapted from Tim Berners Lee’s description of the Semantic Web

35. Knowledge Management Components Components: Strategies Processes Metrics Cycle: Knowledge, Creation Sharing, Measurement And Improvement Technologies: Expert systems Collaboration Training Web Components of Knowledge Management: Components, Cycle and Technologies