By far the most attractive parameter of open source GIS software is the license price, which is usually absent. However, it should be noted that openness is not necessarily a synonym for free and the first paragraph of the definition of open source explicitly states that the method of software distribution: paid or free is the choice of its authors
However, today the vast majority of open source GIS software is distributed completely free of charge. A rare example of an exception is, for example, the ZigGIS extension, which allows you to work with learning gissolution databases in ArcGIS Desktop. The source code of this software is freely distributed for personal use and training, ready-to-use and commercial use requires a license purchase.
Despite the significant difference between the price of licenses for commercial and open source software, it should be borne in mind that the total cost of production and ownership of open source software is nevertheless not zero. Regardless of the type of software, the price should include installation costs, technical support, training and other related costs. The advantage of open source software is that there is no difference between the cost of production and the cost of use. While the price of production of open source software is formed according to similar laws with proprietary, the price formation for the user is fundamentally different (Figure 2).
A good example of the price difference in a specific case is the QGIS open GIS project in the government of the canton of Solothurn (Switzerland). According to preliminary calculations, the savings on licenses alone amounted to about $ 150-200 thousand. However, the project implementers had to spend very significant funds (about $ 30 thousand) to finalize the software product.
Great freedom from the developer .
Open GIS, like open source software in general, reflects the current trend towards decreasing the dependence of the software user on the developer (the so-called vendor lock-in). Obviously, this problem is relative, since the long-term experience of using software, open or closed, one way or another leads to building a technological line around it, the cost of transition from which may turn out to be higher than mastering new software. However, in the condition of openness, the user of open source GIS software is guaranteed the opportunity to make the changes he needs on his own.
ESRI’s past and current refusals to support certain programming languages (VBA, VB6 for ArcGIS 9.4) and software packages in general (Arcview GIS 3.x) are rational from the manufacturer’s point of view, this move allows you to focus on more promising areas of development. However, these steps can also cause dissatisfaction among the users of the products, who, by the time they stopped using them, managed to closely integrate them into their technological lines and work out their support within their organizations. Often, users may not be interested in the new software, but in continuing to support the old one. The openness of GIS software in this case gives great guarantees of continued support for the software product, including by the user himself.
Development model .
Openness makes GIS development more efficient, mainly due to its high modularity. Development is also greatly facilitated through the use of ready-made software components that are actively used in the development of open GIS. For the interface, QT is often used, the ability to work with numerous vector and raster formats – GDAL / OGR, geometric operations, as a rule, are implemented on the basis of the GEOS / GeoTools library, recently other, less complex components needed in GIS, such such as labeling (PAL), projection transformations (Proj.4), high-quality rendering (AGG) and others. This modularity allows you to focus on more efficient implementation of a certain subset of functionality and avoid the duplication of effort inevitable in the case of a closed development model.
The fast pace of development, the attraction of developers from all over the world and the high modularity drive the innovative nature of open source software. Here, the introduction of new, often not yet fully developed technologies, does not meet with opposition, but rather is welcomed. So, for example, support for the very widespread also open spatial databases PostGIS appeared in commercial GIS software Mapinfo and ArcGIS relatively recently. Open GIS has been able to work with these databases for at least 4-5 years. Rapid growth in functionality can affect the reliability and usability of the application, but this can be offset by additional testing by the wider user community.
Long-term control of the situation .
Many of the benefits of open source GIS software listed above can be attributed to proprietary products when there is a good choice. However, if the user is on the market for a long time, only open source software can provide full control over the product in the long term.