Local buffering for OGIS compliant data consumer

In an open GIS environment, a GIS client can access spatial data in different types of GIS servers in the same way. This means that open GIS component software ensures interoperability throughout heterogeneous GIS servers. The user response time, however, tends to increase if the client uses standard interfaces for data accesses that can ensure interoperability. This is because the format of spatial data accessed from a specific GIS server must be transformed into a common format, such as ROWSET in OLE/DB, which is compatible with standard interfaces. We develop efficient techniques for data buffering in the GIS client to reduce response time. The buffer management techniques newly proposed in this paper are characterized by: (1) considering variable sizes of multiple buffers that correspond to multiple layers in the GIS; and (2) creating and managing a spatial index for each layer. We integrate buffer management components into MapBase, open GIS component software, and show that these techniques yield significant performance benefits.