CGDI IN ACTION: EXPLORING QUALITY OF SERVICE

The national GeoConnections program has funded many projects for sharing geospatial information in its priority policy areas public health, public safety and security, environment and sustainable development, and matters of importance to aboriginal communities - resulting in many geospatial Web Services in the Canadian Geospatial Data Infrastructure (CGDI). To build user confidence in using geospatial Web Services in the CGDI for their decision making, knowing the quality of these services is important. In this paper, the authors discuss the results of a GeoConnections-funded project in exploring the Quality of Service (QoS) metrics and applying them to test services in the CGDI. Essential QoS metrics, including availability, reliability, time latency, response speed, performance testing, and load testing, were determined. All these QoS metrics can be dynamically monitored by machines through simulating service requests at certain time intervals. The selection of candidate services for testing were from GeoConnections projects and from services discovered in the GeoConnections Discovery Portal, with the balanced representation from different levels of government and the private sector, communities of interest, and geographic regions. Based on the designed QoS metrics, tests were carried out for these candidate services. The availability and reliability were evaluated using the Federal Geographic Data Committee (FGDC) Service Status Checker. Other QoS metrics - time latency, response speed, performance testing, and load testing - were measured using Proxy Sniffer T. In conclusion, this study proposed and implemented QoS measurement for services in the CGDI. The visibility of service quality will support users in choosing and employing geospatial Web Services in the CGDI for their day-to-day planning and decision making.