SwERVE

Intelliscan's SwERVE is aimed at customers who hold unique data within GIS systems and wish to maximise its availability at minimum cost. SwERVE opens data locked within proprietary systems and makes it available to popular desktop applications with no risk of corruption to the source data. The purpose of SwERVE is to supply an enterprise with access to up-to-date data that is stored and maintained within legacy GIS applications. Figure 1 shows an overview of the SwERVE system.

Figure 1: SwERVE System Overview

SwERVE consists of three components:

• SwERVE Server
• SwERVE Management Console
• SwERVE Client

The SwERVE Server interfaces with the legacy GIS - listening for data requests and responding to those requests. A request may come from the SwERVE Management Console or from a number of SwERVE clients. The Server responds by writing out the requested data in open, standards based files. Communication between the components of SwERVE requires that a shared folder structure be set up on the machine running the SwERVE Server.

The SwERVE Management Console serves as the point of access for a GIS Administrator to the legacy GIS , allowing the underlying data model for the GIS to be determined, extract collections to be defined, and cache and bulk extracts to be performed. The data model is used by all SwERVE components as a means of interpreting the structure of the GIS. Extract collections comprise a definition of the data to be extracted when a client selects that collection. A cache extract allows frequently accessed data to be stored outside the legacy GIS where it can be accessed more efficiently by SwERVE. Bulk extracts are one-off, system wide data extracts which may be used for example for periodic analysis and reporting purposes.

The SwERVE Client is integrated into the desktop GIS allowing client users to extract data from the legacy GIS based on geographic regions. Having selected the data (collection) to extract, an extract is performed by simply drawing a bounding region on screen.

Using SwERVE

Using SwERVE, a subset of data from a GIS table or tables may be extracted based on a spatial boundary, the entire contents may be extracted using a bulk extract facility or differential extracts can be made giving data that has changed since a previous extract. Frequently accessed data may also be cached to optimise the performance of spatial based extracts.

From a client's viewpoint, access to the legacy GIS data is via a collection. A collection is defined by a GIS Administrator and will describe the tables (and their attributes and geometries) to be extracted from the GIS. This type of collection is termed a public collection. Any number of publicly available collections may be defined for one data model. A data model is a description of the legacy GIS data architecture which is built and understood by SwERVE.