Health Level Seven Approves Web Services Profile and ebXML as DSTUs for HL7 Version 3 Transport Specifications
Health Level Seven, Inc. (HL7) HL7 Releases Two Version 3 Transport Specifications as Draft Standards for Trial Use (DSTUs): Web Services and ebXML
Ann Arbor, Michigan, USA. April 27, 2004.
Health Level Seven (HL7) recently announced that two Version 3 (V3) transport specifications — Web Services and ebXML — have passed the ballot stage and have been approved as Draft Standards for Trial Use (DSTUs).
The Web Services and ebXML DSTUs are both being published for a 24-month period of trial use, during which time users will provide to HL7 feedback on their experiences with the standards. This information will be helpful in shaping these standards into more effective documents for the healthcare industry. The documents will then be balloted at the membership level and, if passed, will be submitted to the American National Standards Institute (ANSI) for final approval as HL7 Standards.
Web Services is a way for applications to expose software services using standard interoperability protocols, regardless of the platform on which they are implemented. The development of interoperable standards and the focus on communication and collaboration among people and applications have created an environment where Web Services is becoming the protocol/technology of choice for application integration.
"We developed the Web Services Profile for HL7 in response to an industry need for increased interoperability between implementations and are very excited it achieved DSTU status in only one ballot cycle," says Roberto Ruggeri, editor of the standard and Technical Strategist, Microsoft Healthcare and Life Sciences. "This is the result of a tremendous collaborative effort, which will continue to evolve as we incorporate feedback from across the healthcare community."
There are many definitions of Web Service, but almost all definitions have these things in common:
Web Services expose useful functionality to users through the Web Services protocols.
Web services provide a way to describe their interfaces in enough detail to allow a user to build a client application to talk to them. This description is usually provided in an XML document called a Web Services Description Language (WSDL) document.
Web services are registered so that potential users can find them easily. This is done with Universal Discovery Description and Integration (UDDI).
The Web Services Profile for HL7 promotes the use of Web Services to exchange HL7 messages and to ease interoperability between implementations. The profile focuses on basic Web services protocols and technologies like SOAP (Simple Object Access Protocol) and WSDL (Web Services Description Language), which lay the groundwork for more complex interactions based on higher-level Web services specifications.
ebXML is a specification for message communication in XML developed by the OASIS consortium (www.oasis-open.org). The purpose of the HL7 ebXML transport specification is to provide secure, flexible transport for exchanging HL7 messages between message handling interfaces or ebXML Message Service Handlers (ebXML MSH). It specifies an HL7-specific implementation of the ebXML Message Service as described in "Message Service Specification Version 2.0 1 April 2002". The transport will move HL7 content, messages and documents, as well as legacy standards over a variety of lower level transports, such as TCP/IP, HTML, and SMTP. This protocol optionally supports important features such as Duplicate Message handling, Reliable Messaging, Message Routing, Sequencing, and Digital Signatures. When using this protocol in combination with a certificate based TLS (Transport Layer Security) or SSL (Secure Sockets Layer) TCP/IP lower level transport it provides a robust, secure and authenticated communications infrastructure for exchanging HL7 V2 and V3 messages and content between organizations. It may also be used within organizations to exchange HL7 content, as well as legacy content, over internal networks.
"This protocol allows us to implement a single secure authenticated communications infrastructure for both legacy and emerging message standards," said Paul Knapp, contributing editor of the standard, co-chair of HL7s XML special interest group (SIG), and chief technology officer of Continovation Services Inc. "We can use it to meet current messaging and privacy needs and enable features later such as digital signatures should non-repudiation become a requirement."
Version 3 Background
The Web Services and ebXML transport specifications are only two of over two dozen specifications that make up the Version 3 Messaging Standard. The V3 project represents a new approach to clinical information exchange. It is XML-based and built from the ground up around a single object model, the HL7 Reference Information Model (RIM) and a rigorous methodology that ties model to message and finally to syntax.
The V3 specification is built around subject domains, for each of which it provides storyboard descriptions, trigger events, interaction designs, domain object models derived from the RIM, hierarchical message descriptors (HMDs) and a prose description of each element. Implementation of these domains further depends upon a non-normative V3 Guide and normative specifications for: data types; the XML implementable technical specifications (ITS) or message wire format; message and control "wrappers"; and transport protocols.
Founded in 1987, Health Level Seven, Inc. (http://www.HL7.org) is a not-for-profit, ANSI-accredited standards developing organization dedicated to providing a comprehensive framework and related standards for the exchange, integration, sharing, and retrieval of electronic health information that supports clinical practice and the management, delivery and evaluation of health services. HL7's 2,000 members represent over 500 corporate members, including 90 percent of the largest information systems vendors serving healthcare.
International affiliates have also been established in 24 countries throughout the globe including Argentina, Australia, Brazil, Canada, China, Croatia, Czech Republic, Denmark, Finland, Germany, Greece, India, Ireland, Japan, Korea, Lithuania, Mexico, The Netherlands, New Zealand, Spain, Southern Africa, Switzerland, Taiwan and the United Kingdom.
Health Level Seven, Inc.
Tel: (734) 677-7777
Prepared by Robin Cover for The XML Cover Pages archive. See also "Health Level Seven (HL7) Recently Announced that Version 3 Standard: Patient Administration, Release 1 Has Passed the Ballot Stage and has Been Approved as a Draft Standard for Trial Use (DSTU)."