1
Projects templates ontologies policies Projects templates ontologies policies Projects Templates Ontologies Policies and Sets Interpretations Scenarios Semantics Policy Exchange/ Artifact Sharing Templates Ontologies Policies and Sets Scenarios Taxonomic search Vulcan Forge Highly Scalable Cloud Infrastructure User Management Collaboration Tools Trust Management Infrastructure Management Generator Tools Policy Text Tools Policy Modeling Tools Policy Modeling Tools Policy Makers Policy Makers Policy Makers HIS, HIE, ACO etc. Policy sets for Enforcement Points Collaborative Policy Creation and Analysis HealthCare Organizations HealthCare Organizations Organizations HealthCare Organizations Policy Makers Policy Makers Privacy Advocates and Researchers Privacy Advocates and Researchers Privacy Advocates and Researchers Sharing Collaboration Privacy Policies, HIEs and ACOs Policy Forge Architecture Reasoning Framework using Formula Policy Formalization Problem Screenshots Templates and Semantic Anchoring A Collaborative Environment for Formalizing Privacy Policies in Health Care Andras Nadas, Tihamer Levendovszky, Laszlo Juracz, Janos Sztipanovits, Mark E. Frisse, Ann J. Olsen Not feasible for Large sets of policies Multiple systems/semantics Verification/Validation Policies Policies Inst. Policies Policies Policies State Policies Hand written Code Read and Understand Think and Write Policies Policies Federal Policies Hand written Code Polici es Generated Code Read and Understand Read Formal Policy Models Think Write Polici es Read and Understand Think Polici es Read and Understand Think To make it scale: Divide and Conquer approach for the human aspects Formal Model Representation for the technical issues Ontologies represent the formal knowledge base Documents from the library can be annotated by ontology terms Words and expressions from the text can be used to create elements in an ontology. Ontologies can be imported from standards (rdf-owl and json-ld). Uses imported templates as the language. Multiple languages can coexist and can be combined if their representation and semantics enables it. We prefer graphical languages but textual languages will also be supported(as long as they are formal and meets environmental constraints.) Use Cases are simple clinical workflows represented on a timeline. Concentrates on data flows between systems and accesses by users. The dataflow is check to conform to a selected set of policies. The policy set is also checked for internal consistency. Patterns: <structure> || <ontology>||<logics> Example: SUBJECT allowed to perform OPERATION on OBJECT given that CONSTRAINT are met SUBJECT,OPERATION and OBJECT are defined by ontologies ACCESS CONDITIONS are defined with first order logic expressions RESTRICTIONS are defined with first order logic constraints Execution/Analysi s Domains Translators Policies PATRN Policy Text FORMUL A, prolog, Etc. Model Translator (execution domain specific) Ontologie s Template s Policy Models Semantic anchors Execution domain specification Policy Patterns Building Blocks Specialization Federal, State, Institutional Privacy Policies 1. Recognize the common patterns used in the textual policy descriptions. These patterns will form the templates in PATRN. 2. Compile the object and actors of the policies and organize them into ontologies. 3. Formal policy models are composed from the templates and ontologies. 4. Using the semantic anchors, the formal policy models can be translated for analysis or enforcement. Instance Model Metamodel Semantic Domain (Term Algebraic Representation) Semantic Models (Formal Structures in Term Algebra) Instance Model (Term Algebraic Representation) Metamodel (Term Algebraic Representation) Semantic Mapping Rules (Logic Programs) Semantic Mapping (Execution of Logic Programs) Specifies Defines Defines Instantiates Intuitions, standards, and variations Updates, Revisions extensions Testing and verificatio n Specification for Operational Semantics (Logic Program) Grounding Denotational Semantics in Mathematics Structural Constraints Structural Constraints FORMULA Specification Symbolic Execution SMT Formula Guess symbolic world Add symmetry breaking Z3 Solver Pick next region Encode solution region Try something new Use state-of-the-art satisfiability modulo theories (SMT) solver Z3 to solve quantifier-free formulas. Open World Reasoning: Facts and Rules Open World Queries P?G: Find a closure of the program by ground facts where a goal is satisfied. E. g. “Is document id accessible by x?" P[F]: Partially close P with facts F and remove “new” marking from all associated data types. E.g. Can x access any documents? Term Algebraic Data Types Formula adds data types to logic programming Data types are “algebraic”, i.e. they are functions that create data A data constructor always constructs the same value when provided the same arguments Two values are the same if and only if they were constructed by the same constructor with the same arguments A system for modeling with logic Generic; not specifically designed to model software. Specifications are written as “open-world” logic programs. FORMULA 2.0 can verify, synthesize, transform, compile and check models all with logic Z3 SMT Solver 1. K. Krasnow Waterman at MIT Pre-processing Legal Text: Policy Parsing and Isomorphic Intermediate Representation 2. Helen Nissenbaum: Contextual Integrity 3. Mitchell, Datta (Stanford and CMU’s) Policy Formalization in Prolog Policy Forge Workflow Privacy Policies: Federal (HIPAA, HITECH, Omnibus) State (Mental Health, Genetics, STD, HIV, etc.) Institutional (Notice of Privacy Practices, IRBs, etc. ) Patient Preferences (Opt-out) Increased punishment for privacy validation Increased risk aversion of institutional policy makers Health Information Exchanges (HIEs): Increased adoption of EHRs Pressure for more affordable care Move towards coordinated care Accountable Care Organizations (ACOs) More pressure for sharing health information Conflicts with risk aversion Develop an engineering method that provides the right provisions to enable functioning HIEs of all size. Read and Understand Policy Formalization is complex… 1 Have to understand legal domain, context and language Have to understand formal domain, context and language … but feasible for a small set of policies and experimentation 2,3 . Hand written Code Read and Understand Think and Write Policies SHARPS Team for Research in Ubiquitous Secure Technology

A Collaborative Environment for Formalizing Privacy ... · Use state-of-the-art satisfiability modulo theories (SMT) solver Z3 to solve quantifier-free formulas. • Open World Reasoning:

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Page 1: A Collaborative Environment for Formalizing Privacy ... · Use state-of-the-art satisfiability modulo theories (SMT) solver Z3 to solve quantifier-free formulas. • Open World Reasoning:

Projects

− templates − ontologies − policies

Projects

− templates − ontologies − policies

Projects

Templates Ontologies

Policies and Sets Interpretations

Scenarios Semantics

Policy Exchange/ Artifact Sharing

Templates Ontologies

Policies and Sets Scenarios

Taxonomic search

Vulcan ForgeVulcan ForgeVulcan Forge Vulcan ForgeVulcan Forge

Highly Scalable Cloud Infrastructure

User Management Collaboration Tools Trust Management Infrastructure

Management

Generator Tools Policy Text Tools Policy Modeling Tools

Policy Modeling Tools

Policy Makers Policy Makers Policy Makers

HIEs HIEs HIS, HIE, ACO etc.

Policy sets for Enforcement

Points

Collaborative Policy Creation and Analysis

Vulcan ForgeVulcan Forge

and Analysis

HealthCare Organizations

and Analysis

HealthCare Organizations Organizations

HealthCareOrganizations

HealthCare Organizations

Policy MakersPolicy MakersPolicy Makers

Privacy Advocates and Researchers

Privacy Advocates and Researchers

Privacy Advocates and Researchers

Sharing CollaborationSharing Collaboration

Privacy Policies, HIEs and ACOs Policy Forge Architecture

Reasoning Framework using Formula Policy Formalization Problem

Screenshots

Templates and Semantic Anchoring

A Collaborative Environment for Formalizing Privacy Policies in Health Care Andras Nadas, Tihamer Levendovszky, Laszlo Juracz, Janos Sztipanovits, Mark E. Frisse, Ann J. Olsen

… Not feasible for• Large sets of policies• Multiple systems/semantics• Verification/Validation

PoliciesPoliciesInst.Policies

PoliciesPoliciesStatePolicies

Hand written CodeRead

andUnderstand Think

andWrite

PoliciesPoliciesFederalPolicies

Read

Hand written Code

FormalPolicy

Models

FormalPolicy

Models

Policies Generated

Code

Readand

Understand ReadFormalPolicy

Models

Think Write

Policies

Readand

Understand

Think

Policies

Readand

Understand Think

To make it scale: Divide and Conquer approach for

the human aspects Formal Model Representation for

the technical issues

• Ontologies represent the formal knowledge base

• Documents from the library can be annotated by ontology terms

• Words and expressions from the text can be used to create elements in an ontology.

• Ontologies can be imported from standards (rdf-owl and json-ld).

• Uses imported templates as the language.• Multiple languages can coexist and can be

combined if their representation and semantics enables it.

• We prefer graphical languages but textual languages will also be supported(as long as they are formal and meets environmental constraints.)

• Use Cases are simple clinical workflows represented on a timeline.

• Concentrates on data flows between systems and accesses by users.

• The dataflow is check to conform to a selected set of policies. • The policy set is also checked for internal

consistency.

Patterns: <structure> || <ontology>||<logics> Example:

SUBJECT allowed to perform OPERATION on OBJECT given that CONSTRAINT are met

SUBJECT,OPERATION and OBJECT are defined by ontologiesACCESS CONDITIONS are defined with first order logic expressionsRESTRICTIONS are defined with first order logic constraints

Execution/Analysis Domains

TranslatorsPolicies PATRN

Policy Text FORMUL

AFORMUL

AFORMUL

AFORMULA, prolog,

Etc.

ModelTranslator(execution

domain specific)

Ontologies

Templates

Policy Models

Semantic anchors

Execution domain

specification

Ontologie

TemplatePolicy

PatternsPolicy

Semantic

Template

Policy ModelsModels

Semantic

Policy A, prolog,

Building Blocks Specialization

Federal, State,

Institutional Privacy Policies

1.Recognize the common patterns used in the textual policy descriptions. These patterns will form the templates in PATRN.

2.Compile the object and actors of the policies and organize them into ontologies.

3.Formal policy models are composed from the templates and ontologies.

4.Using the semantic anchors, the formal policy models can be translated for analysis or enforcement.

Instance Model Metamodel

Semantic Domain

(Term Algebraic Representation)

Semantic Models (Formal

Structures in Term Algebra)

Instance Model (Term Algebraic Representation)

Metamodel (Term Algebraic Representation)

Semantic Mapping Rules

(Logic Programs)

Semantic Mapping (Execution of Logic

Programs) Specifies

Defines

Defines

Instantiates

Intuitions, standards,

and variations

Updates, Revisions extensions

Testing and

verification

Specification for Operational Semantics

(Logic Program)

Grounding Denotational Semantics in Mathematics

Structural Constraints

Structural Constraints

FORMULA Specification

Symbolic Execution SMT Formula

Guess symbolic world

Add symmetry breaking Z3 Solver

Pick next region

Encode solution region

Try something new

Use state-of-the-art satisfiability modulo theories (SMT) solver Z3 to solve quantifier-free formulas.

• Open World Reasoning:• Facts and Rules• Open World Queries

• P?G: Find a closure of the program by ground facts where a goal is satisfied. E. g. “Is document id accessible by x?"

• P[F]: Partially close P with facts F and remove “new” marking from all associated data types. E.g. Can x access any documents?

• Term Algebraic Data Types• Formula adds data types to logic programming• Data types are “algebraic”, i.e. they are functions that create data• A data constructor always constructs the same value when

provided the same arguments• Two values are the same if and only if they were constructed by the

same constructor with the same arguments

• A system for modeling with logic• Generic; not specifically designed to model software.• Specifications are written as “open-world” logic programs.• FORMULA 2.0 can verify, synthesize, transform, compile and

check models all with logic• Z3 SMT Solver

1. K. Krasnow Waterman at MIT Pre-processing Legal Text: Policy Parsing and Isomorphic Intermediate Representation 2. Helen Nissenbaum: Contextual Integrity3. Mitchell, Datta (Stanford and CMU’s) Policy Formalization in Prolog

Policy Forge Workflow

Privacy Policies:• Federal (HIPAA, HITECH, Omnibus)• State (Mental Health, Genetics, STD, HIV, etc.) • Institutional (Notice of Privacy Practices, IRBs, etc.)• Patient Preferences (Opt-out)

• Increased punishment for privacy validation• Increased risk aversion of institutional policy makers

Health Information Exchanges (HIEs):• Increased adoption of EHRs• Pressure for more affordable care• Move towards coordinated care

• Accountable Care Organizations (ACOs)

• More pressure for sharing health information• Conflicts with risk aversion

Develop an engineering method that provides the right provisions to enable functioning HIEs of all size.

Readand

Understand

Policy Formalization is complex… 1

• Have to understand legal domain, context and language• Have to understand formal domain, context and language… but feasible for a small set of policies and experimentation 2,3.

Hand written Code

Readand

Understand

Thinkand

WritePolicies

SHARPS

Team for Research in Ubiquitous Secure Technology