Date Added: Jan 2013
In current system Web Map Service (WMS) provides spatial information to Internet users by map images. Commonly, spatial data are stored as vector data. It is a long time job to calculate the density of pixels before distribution and create map images from vector data. To reduce the time and cost, the authors employ Linux cluster. When a map is requested, coordinates scope that is a rectangle defined with xmin, ymin, xmax, ymax must be specified. They design a load balance algorithm to divide the request rectangles into some sub-rectangles. Each sub rectangle is send to a WMS node to produce some sub-maps.