Case Study

Public Health: Clinical Surveillance Web Services

Background

A government health organization provides web service based interfaces that enable public health organizations to efficiently perform clinical surveillance regarding trends in public health. The technical infrastructure provides a transport mechanism that securely transmits public health related documents amongst health organizations and uses a combination of SOAP and ebXML to provide a transport mechanism that is independent of the document type and file content.

Challenges

The objective was to determine the capacity and scalability of the file transport web service with the intentions of providing guidelines for optimal software configurations and infrastructure sizing guidelines required to support a growing consumer base.

Strategy

Automate the business processes of invoking the file transmission using the targeted transport web service and executing a series of performance/scalability tests of varying levels of system load.

Solution

RTTS provided an automated framework for testing the messaging web service under varying levels of concurrent usage.

  • Business processes were automated in a manner that could vary the size of the document being transferred, as well as account for the different levels of security applied to the document transfer.
  • Tests were modeled and executed based upon a thorough understanding of the pertinent health organizations characteristics, such as the distribution of document sizes that are transferred on a daily basis.
  • System resources were monitored on each server component in order to determine the health of the systems, as well as the capacity of the system.
  • Initial testing revealed instability within the transport mechanism that began with 40 concurrent health organizations transmitting documents. At this level of usage the application encountered transport retries. Beyond 40 concurrent health organizations the reliability of the transport mechanism was undermined.
Public Health Figure 1

Benefits

  • The approach to business process automation permitted re-usable test assets that could test varying permutations of file transfers, security policies and system configurations. This added to the viability of the automated testing approach that could withstand application changes over the lifetime of the web service software.
  • The testing strategy provided sufficient exposure of the file transport infrastructure and the relationships between its system resource utilization and the service demands of its consumer end-points. Bottlenecks could be effectively identified and system capacity could be sized appropriately.