The greatest performance advantage of a TatukGIS DK.ASPNET developed web GIS application is it is “stateless”, meaning data is not held between user requests. Although this precludes some advanced functional possibilities, the stateless nature of the DK.ASPNET offers a very high capacity for handling large numbers of simultaneous users – even 1,000’s - from a single server.
The main advantages of the DK.VCL + IntraWeb (DK+IW) option to develop a web GIS solution is the opportunity for Delphi or C++Builder developers to create a web application (or port a DK based desktop application to the web) without changing development technologies. A DK+IW application can offer a user experience that feels nearly the same as a desktop application, including use of in-memory layers. The feel might be compared to the user experience with a “temporary terminal session”. As a single executable, the end customer can be prevented from altering or customizing the web GIS application, thereby enhancing the security of the technology behind the application and simplifying off-the-shelf deployment.
The trade-off for the high level of functionality with the DK+IW option is the relatively greater consumption of memory resources on the server, because the application holds information between user requests. The degree of server memory consumption depends on the nature of the application. The developer must keep in mind the number of intended concurrent users and the effect of the design of the application on the consumption of memory resources. The simultaneous user capacity constraints are difficult to define because this depends on the specifics of any given application. The DK+IW option might not be appropriate, for example, for a public web server required to support 1,000’s of simultaneous users, but might work well for a server application supporting up to 100 simultaneous users per server.
The guidance provided here is specific to use of IntraWeb with the TatukGIS DK.VCL product (and the TatukGIS DK.VCL + IntraWeb Component) for GIS web server applications. This guidance does not address use of IntraWeb in situations not involving TatukGIS products.