Secure Sharing of Electronic Health Records in Clouds

Transcription

1 Secure Sharing of Electronic Health Records in Clouds Ruoyu Wu, Gail-Joon Ahn Arizona State University Hongxin Hu Delaware State University The Laboratory of Security Engineering for Future Computing (SEFCOM) URL : sefcom.asu.edu BYENG 486 ASU

2 Outline Introduction Problem Summary Broker-based Composite EHRs Authorization System Design Implementation and Evaluation Related Work Conclusion and Future Work Q & A Slide 2

3 Internet-centric Cloud-driven World SaaS Ecosystem PaaS IaaS Slide 3

4 Healthcare Evolution Paper-based records transform to EHRs EHRs are shifting to Clouds Transform Shift Paper-based Sharing Efficiency Ubiquitous Access EMRs Cost Efficiency Dynamic Scalability Cloud Platform Slide 4

5 Security and Privacy Identity Management Authentication Trust Management Policy Management Compliance Management Access Control H. Takabi, J. Joshi, and G. Ahn. Security and privacy challenges in cloud computing environments. Security & Privacy, IEEE, 8(6):24 31, Slide 5

6 Access Control Issue Cross-domain EHRs integration Diversity of healthcare practitioners Slide 6

7 Hypothesis We propose a broker-based authorization approach which supports selective sharing of composite EHRs Logical EHR model EHR data schema composition Cross-domain EHR instance aggregation Access control policy specification Slide 7

8 Broker-based Composite EHRs Authorization Overview Slide 8

9 Logical EHR Model An EHR object is represented as a tuple T = (r, V, E) r is the root of the whole EHR object; V is a set of nodes within the whole EHR object hierarchical structure E V V is a set of links between nodes. Slide 9

10 EHR Data Schema Composition Slide 10

11 Algorithm for Merging Two EHR Data Schemas Slide 11

12 EHR Data Schema Composition Example r s T s m r d m T d m Merge to Call insertsubschema(t d, r d, T s, r s ) r d = r s -> m = r d Otology Classes Demographic, Demo Gender, Sex DoB, Birthday, Birth Date Slide 12

13 EHR Data Schema Composition Example Slide 13

14 Cross-domain EHR Instance Aggregation Slide 14

15 Policy Specification An access control policy is a tuple acp= (sub, obj v, pur, effect), where A subject sub is defined as a tuple sub = <u, so > or sub = <r, so >; An object obj v is a set of nodes in a sub-schema of T rooted at node v; pur is a set of business practices in healthcare domains; effect {permit,deny} is the authorization effect of the policy. Examples: P1: (<GP, h1>, obj Encounters, {treatment}, permit) P2: (<SP, h2>, obj Medications, {treatment,research}, permit) P3: (<Dr.Nic, h2>, obj Labs, research, deny) Slide 15

16 Policy Specification Cont d Slide 16

17 System Design System Architecture Slide 17

18 Case Study Scenario illustration Slide 18

19 System workflow Case Study - Cont d Slide 19

20 Implementation Cloud environment illustration Slide 20

21 Implementation-Cont'd Home Page & Policy Specification Page Slide 21

22 Implementation-Cont'd Patient Discovery Page & Composite EHRs Access Page Slide 22

23 Implementation-Cont'd CONNECT implementation details Slide 23

24 Evaluation Analyze efficiency and scalability Slide 24

25 Related Works Selective EHRs sharing Presented a patient-centric authorization framework to secure the sharing of electronic health records[jin'09][jin 11]. Secure EHRs in cloud computing Proposed a patient-centric digital right management (DRM) approach to protect privacy[jafari 11]. Presented a security model for healthcare application clouds[zhang'10]. Presented patient-centric and fine-grained access control mechanism for securing personal health records in cloud computing[li'10]. Slide 25

26 Conclusion & Contributions We articulate access control issues in healthcare cloud computing environments. A broker-based authorization approach has been presented, which supports selective EHRs sharing. A prototype cloud-based EHRs sharing system has been designed, implemented and evaluated to demonstrate the effectiveness and efficiency of our proposed approach. Slide 26

27 Future Work We would conduct more comprehensive evaluations on our system with real-world healthcare datasets. We would investigate how to address policy composition issues and how to support fine-grained delegation mechanism for EHRs in cloud computing environments. In addition, we would like to apply our approach to support EHRs sharing using consumer devices such as smart phone and tablet to cover border sections of the whole healthcare ecosystem. Slide 27

28 Questions Slide 28