Single line street network: The foundation of Mobile GIS

The single line street network (SLSN) is a model, or abstraction, of the derivable surface and selected linear features in a city or a region. The major roles of the SLSN in Mobile Geographic Information Systems (GIS) are: 1) to provide the underlying framework of positioning and navigating vehicles; 2) to provide location reference to road related information; 3) to act as a visual index for display and query; and 4) to link to attribute information. The SLSN is an intelligent, topologically structured database. The construction of the SLSN in the City of Scarborough, its data model, data loading and maintenance issues, and how the SLSN can relate attributes to spatial objects for vehicle navigation and information systems (VNIS) are described. A municipal government´s contribution to VNIS and its view on partnership with private sector and external agencies in building a Mobile GIS are examined.