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Building Trustworthy Semantic Webs Dr. Bhavani Thuraisingham The University of Texas at Dallas Semantic web technologies for secure interoperability and digital libraries March 2010 Outline Secure Digital libraries and semantic web Secure heterogeneous/federated data management and semantic web Secure web portals Secure Web data/information management Secure data models - Secure XML, RDF, - - - - Relational, object-oriented, text, images, video, etc. Secure data management functions - Secure query, transactions, storage, metadata Key components for secure digital libraries and information retrieval/browsing Secure Web Database Functions Secure Query Processing Secure Transaction Management Secure Storage Management Secure Web Data Security and Integrity Secure Metadata Management Management Secure Data Warehousing Secure Interoperability Secure Web Mining Secure Query Management: Language Issues Query language to access the databases - SQL extensions are being examined - XML-based query languages combined with SQL are emerging Example: XML-QL - Querying RDF Data XML extensions for Multimedia databases such as SMIL (Synchronized Multimedia Interface Language) - Mappings between multiple languages Web rules and query languages developed by W3C Security should be incorporated into all aspects Security/Integrity Management Support for flexible security policies Negotiations between different database administrators Authorization and access control models such as role- based access control Identification and authentication Privacy Control Copyright protection / Plagiarism Maintaining the quality of the data coming from foreign sources Represent data and policies in XML, RDF, OWL and reason to determine quality and ensure security Secure Digital Libraries Digital libraries are e-libraries - Several communities have developed digital libraries Medical, Social, Library of Congress Components technologies - Web data management, Multimedia, information retrieval, indexing, browsing, -- - Security has to be incorporated into all aspects - Secure models for digital libraries, secure functions Secure Information Retrieval Secure Query Processor Secure Metadata Manager Secure Update Processor Secure Browser/ Editor Secure Storage Manager Security/ Integrity Manager Secure Browsing Browser augments a multimedia system to develop a hypermedia system Search space consist of nodes and links with different access control rules and/or classification levels May be represented as RDF Graphs Can a user traverse a link or access the contents of a node? - What authorization does he/she have? Interoperability of Heterogeneous Database Systems Database System A Database System B (Relational) (ObjectOriented) Network Transparent access to heterogeneous databases both users and application programs; Query, Transaction processing Database System C (Legacy) Technical Issues on the Interoperability of Heterogeneous Database Systems Heterogeneity with respect to data models, schema, query processing, query languages, transaction management, semantics, integrity, and security policies Federated database management - Collection of cooperating, autonomous, and possibly heterogeneous component database systems, each belonging to one or more federations Interoperability based on client-server architectures Federated Database Management Database System A Database System B Federation F1 Cooperating database systems yet maintaining some degree of autonomy Federation F2 Database System C Schema Integration and Transformation in a Federated Environment External Schema 1.1 External Schema 2.1 External Schema 1.2 Federated Schema for FDS - 2 Federated Schema for FDS - 1 Export Schema for Component A Generic Schema for Component A Component Schema for Component A External Schema 2.2 Export Schema I for Component B Export Schema II for Component B Export Schema for Component C Generic Schema for Component B Generic Schema for Component C Component Schema for Component B Component Schema for Component C Adapted from Sheth and Larson, ACM Computing Surveys, September 1990 Transforming Secure Data Models EMP: Level = Secret SS# Ename Salary D# 1 John 20K 10 2 Paul 30K 20 3 Mary 40K 20 Class EMP is Secret It has 3 instances: John, Paul and Mary Class DEPT is Unclassified DEPT Mgr Level It has 2 instances Math and Physics D# Dname 10 Math Smith U Math is Unclassified 20 Physics Jones C Physics is Confidential Secure Schema Integration Security must be maintained during transformations Layer 5 Layer 4 Layer 3 Layer 2 Layer 1 External schemas: Schemas for the various classes of users Federated schemas: integrate export schemas of the components of the federation Export schemas for the components: e.g., export schemas for components A, B, and C (note: component may export different schemas to different federations) Generic schemas for the components: e.g., generic schemas for components A, B, and C Secure Schemas at the Component level: e.g., Component schemas for components A, B, and C Security Policy Integration Layer 5 Layer 4 Layer 3 Layer 2 Layer 1 External policies: Policies for the various classes of users Federated policies: integrate export policies of the components of the federation Export policies for the components: e.g., export policies for components A, B, and C (note: component may export different policies to different federations) Generic policies for the components: e.g., generic policies for components A, B, and C Policies at the Component level: e.g., Component policies for components A, B, and C Federated Data and Policy Management Data/Policy for Federation Export Data/Policy Export Data/Policy Export Data/Policy Component Data/Policy for Agency A Component Data/Policy for Agency C Component Data/Policy for Agency B Inference Control Federated Inference Controller Federated Data Management Export Engine Export Engine Export Engine Inference Controller Component Data System for Agency A Inference Controller Inference Controller Component Data System For Agency C Component Data System for Agency B Applications of Semantic Web Technologies Specify generic policies and schema in RDF, OWL Integrate the generic policies and schemas for federated policies and schemas Apply reasoning strategies for RDF and OWL for inference control in distributed environments What are web portals? A portal, or enterprise information portal (EIP), is a Web site that integrates an organization's knowledge base and all related applications into a single user-customizable environment. This environment acts as a one-stop shop, or "gateway," for users' information and system needs. An organization's entire content database; search facilities; collaboration tools; individual department, workgroup, and project-specific intranets; online applications; and security mechanisms fused into one cohesive environment that's accessible from a single starting point. Enterprise information portals gives large amounts of disparate content and applications unity and continuity. EIP differs from say a well-developed content managed intranet with respect to “personalization”. Personalization EIP differs from say a well-developed content managed intranet with respect to “personalization”. EIPs allow users to customize their portal environment to deliver only the content they're interested in. This means every user who logs onto the portal will have a different view of the system and its content. For example, a Human Resources Manager will not need to see revisions of some engineering drawing but would like to receive news on the latest salary compensation trends. My Yahoo! and MSN are good examples of Internet portals. EIPs are developed specifically to work within business environments, often integrating standard corporate collaboration tools e-mail, shared calendars, discussion forums, and online meetings into the suite . Virtual Workspaces Portals are important for knowledge sharing and virtual workspaces Firms are increasingly leveraging their globally distributed knowledge resources through deployment of distributed teams. Since face-to-face meetings are increasingly less common among distributed teams, team members are more frequently sharing their knowledge through the use of “virtual workspaces” Virtual workspaces are an integrated set of tools that offer a variety of communication support capabilities including a common team repository organized for easy search and retrieval, application sharing, electronic whiteboards and group discussion forums Security and privacy policies determine what information is shared and with whom Semantic Web Applications for Web Portals Web portals and Mashups – Web 2.0 and beyond Utilizes semantic web technologies for information representation and reasoning RDF and OWL technologies ate being used Security investigation for web portals and Mashups is relatively new Need to develop appropriate policies, represent them using semantic web technologies