Design strategies to improve performance of GIS Web services

GIS systems are ubiquitous distributed systems, since geo-spatial information adheres to almost everything. Considering the characteristics of GIS, the following four design-decision issues are particularly crucial: transactional mode (synchronous versus asynchronous), service granularity (finegrained versus coarse-grained), delivery manner (chunk versus stream), and transmission formats (GML versus binary). We have shared our experience in making choices in these four dimensions.