Integrating the Healthcare Enterprise

1. Integrating the Healthcare Enterprise Enterprise User AuthenticationandConsistent Time Glen MarshallCo-Chair, IHE IT Infrastructure Planning Committee

2. IHE IT Infrastructure 2004-2005 Personnel White Page New Access to workforcecontact information New Retrieve Information for Display Retrieve Information for Display Cross-Enterprise Document Sharing Access a patient’s clinical information and documents in a format ready to be presentedto the requesting user Access a patient’s clinical information and documents in a format ready to be presentedto the requesting user Registration, distribution and access across health enterprises of clinical documents forming a patient electronic health record Patient Demographics Query New Audit Trail & Node Authentication New Centralized privacy audit trail and node to node authentication to create a secured domain. Enterprise User Authentication Enterprise User Authentication Consistent Time Provide users a single nameand centralized authentication processacross all systems Coordinate time across networked systems Patient Synchronized Applications Synchronize multiple applications on a desktop to the same patient Patient Identifier Cross-referencing for MPI Patient Identifier Cross-referencing for MPI Map patient identifiers across independent identification domains Map patient identifiers across independent identification domains IHE Interoperability Workshop

3. IHE IT Infrastructure 2004-2005 Personnel White Page New Access to workforcecontact information New Retrieve Information for Display Retrieve Information for Display Cross-Enterprise Document Sharing Access a patient’s clinical information and documents in a format ready to be presentedto the requesting user Access a patient’s clinical information and documents in a format ready to be presentedto the requesting user Registration, distribution and access across health enterprises of clinical documents forming a patient electronic health record Patient Demographics Query New Audit Trail & Node Authentication New Centralized privacy audit trail and node to node authentication to create a secured domain. Enterprise User Authentication Enterprise User Authentication Consistent Time Provide users a single nameand centralized authentication processacross all systems Coordinate time across networked systems Patient Synchronized Applications Synchronize multiple applications on a desktop to the same patient Patient Identifier Cross-referencing for MPI Patient Identifier Cross-referencing for MPI Map patient identifiers across independent identification domains Map patient identifiers across independent identification domains IHE Interoperability Workshop

4. Enterprise User AuthenticationScope • Support a single enterprise governed by a single set of security policies and having a common network domain. • Establish one name per user to be used for all IT applications and devices. • Facilitate centralized user authentication management. • Provide users with single sign-on. IHE Interoperability Workshop

5. Enterprise User AuthenticationValue Proposition • Meet a basic security requirement • User authentication is necessary for most applications and data access operations. • Achieve cost savings/containment • Centralize user authentication management • Simplify multi-vendor implementations • Provide workflow improvement for users • Increase user acceptance through simplicity • Decrease user task-switching time. • More effective security protection • Consistency and simplicity yields greater assurance. IHE Interoperability Workshop

6. Consistent TimeScope and Value Proposition • Meet a basic security requirement • System clocks and time stamps of the many computers in a network must be synchronized. • Lack of consistent time creates a “security hole” for attackers. • Synchronization ±1 second is generally sufficient. • Achieve cost savings/containment • Use the Network Time Protocol (NTP) standard defined in RFC 1305. • Leverage exisisting Internet NTP services, a set-up option for mainstream operating systems. IHE Interoperability Workshop

7. Enterprise User Authentication Use Case: Single Sign On • Motivation • Users need to frequently communicate with many non-integrated IT application services. • Managing multiple user identities and passwords is costly to users and system administration. • Solution • EUA supports a single common user identity for browser-based applications. • EUA allows multiple user authentication technologies. • EUA uses well-trusted standardized user identity mechanisms: Kerberos and CCOW user context. IHE Interoperability Workshop

8. Enterprise User Authentication Use Case: Fast User Switch • Motivation • Customer requirement for fast user switching on a multi-user workstation due to long startup times during normal system login • Solution • Initiate a “null user” during workstation startup. • Utilize EUA to authenticate actual users once, e.g., at start of work shift, via Kerberos. • Utilize Follow Context to switch user identities without incurring the high startup costs, via CCOW user context. IHE Interoperability Workshop

9. Enterprise User AuthenticationKey Attributes • Limited network overhead • Kerberos is network-efficient, developed at a time when high-speed networks were rare. • CCOW is similarly network-efficient • Kerberos and CCOW work with any user authentication technology • Tokens, biometric technologies, smart cards, … • Specific implementations require some proprietary components, e.g., biometric devices. • Once user authentication is complete, network transactions are the same for all technologies. IHE Interoperability Workshop

10. Enterprise User Authentication Key Attributes • Multi-year roll-out • 2004: • Kerberos Server • HTTP Authentication • Shared Identity through CCOW • Grouped with Consistent Time • Future: • DICOM (Supplement 99) • HL7 (v2.6 UAC segment or WSDL/SOAP transport) • CCOW – Kerberos service ticket as part of use context IHE Interoperability Workshop

11. EUA and CTKey Technical Properties • Standards Used • Kerberos v5 (RFC 1510) • Stable since 1993, • Widely implemented on current operating system platforms • Successfully withstood attacks in its 10-year history • Fully interoperable among all platforms • HL7 CCOW, user subject • Network Time Protocol (RFC 1305) • Minimal Application Changes • Eliminate application-specific, non-interoperable authentication • Replace less secure proprietary security techniques • Leverage NTP interfaces built-into operating systems IHE Interoperability Workshop

12. Enterprise User AuthenticationTransaction Diagram IHE Interoperability Workshop

13. Enterprise User AuthenticationTransaction Diagram: CCOW Option IHE Interoperability Workshop

14. Consistent TimeTransaction Diagram Time Server Maintain Time [ITI-1]↑ Time Client IHE Interoperability Workshop

15. Enterprise User Authentication Kerberos Authentication Communication Initiated Initial username, password Request TGT “kinit” Kerberos Server Response (contains TGT) TGT Cache Request Service ticket TGT Response with Service Ticket application Application server Protocol specific communication, using Service Ticket as authenticator Single System Environment IHE Interoperability Workshop

16. Enterprise User Authentication HTTP Authentication Client Authentication Agent HTTP Client Kerberos Authentication Server HTTP KerberizedServer HTTP Get – with no authentication. Start HTTP Session 401 response (WWW Authenticate: Negotiate) Get Kerberos Service Ticket Service Ticket HTTP Get – Kerberized Communication HTTP Response IHE Interoperability Workshop

17. Enterprise User Authentication Fast User Switch Kerberos Authentication Server Client Authentication Agent User Context Participant Context Manager Join Context Join Context User A Login Change Context Change Context Follow Context Follow Context Switch to User A User B Login Switch to User B Device with Fast User Switching IHE Interoperability Workshop

18. Kerberos Documentation • Online • “Moron’s Guide” http://www.isi.edu/gost/brian/security/kerberos.html • MIT Sitehttp://web.mit.edu/kerberos/www/ • Various Microsoft MSDN support documents • Hardcopy • Kerberos, by Brian Tung, Addison Wesley • Various vendor manuals • Configuration and API documentation • Microsoft, Unix, and other vendor documentation IHE Interoperability Workshop

19. HTTP Documentation • Internet draft for Kerberization of HTTP • draft-brezak-spnego-http-05.txt • Other documentation • http://support.microsoft.com/default.aspx?scid=kb;ben-us;326985 IHE Interoperability Workshop

20. EUA FuturesHL7 CCOW Proposal • EUA defines a CCOW identity space • User.Id.Logon.Kerberos • This enables some single signon capabilities. • CCOW exchange of SAML assertions • Assertions can contain Kerberos service tickets • Is an HL7 work item, now underway • Use cases are needed in order to move this forward. IHE Interoperability Workshop

21. EUA FuturesHL7 v2.6 Proposal • HL7 v2.6 User Authentication Credential (UAC) segment • Kerberos service tickets or SAML assertion • User identified associations enables • Better Audit logs • User specific customizations • User specific authorization • HL7 also allows EUA as part of WSDL/SOAP, via SAML assertion IHE Interoperability Workshop

22. EUA FuturesDICOM Proposal • DICOM Associations convey user identification • User identified associations enable • Better audit logs • User specific customizations • User specific authorization • Under development as Supplement 99 IHE Interoperability Workshop

23. More information…. • IHE Web sites: http://www.himss.org/IHE http://www.rsna.org/IHE http://www.acc.org/quality/ihe.htm. • Technical Frameworks: • ITI V1.0, RAD V5.5, LAB V1.0 • Technical Framework Supplements - Trial Implementation • May 2004: Radiology • August 2004: Cardiology, IT Infrastructure • Non-Technical Brochures : • Calls for Participation • IHE Fact Sheet and FAQ • IHE Integration Profiles: Guidelines for Buyers • IHE Connect-a-thon Results • Vendor Products Integration Statements IHE Interoperability Workshop