The New Age of Topographic Data - Management and Access

The Centre for Topographic Information in Sherbrooke (CTIS) has reviewed the way it produces (or updates), manages, and disseminates vector topographic data (NTDB data and others). First of all, the clientele was broken down into segments in order to better respond to specific needs (specialized customers, privileged customers, the general public, and crisis managers). We defined new vector data specifications taking into account customer requirements to a greater degree (update cycle, accuracy, accessibility, change management). International standards (ISO/OGC) were used to better describe data characteristics and to make use of concepts familiar to the geomatics community. Landsat 7 and GPS technology have been used to produce the initial version of this new geospatial data. The NTDB data (150 Gb) and the upcoming data will be stored in a database management system (Oracle8I Spatial). The spatial data will be available in several GIS formats through Web sites using e-commerce technology. This paper focuses on the characteristics of these new Geospatial Database (GDB) specifications, with particular emphasis on spatial relationship expressed by the Dimensionally Extended Nine-Intersection Model (DE-9IM), update management (historical data), and data access.