As a CEN standard with international support independent of any one supplier, and a process to support future evolution NeTEx offers an inherent degree of protection of investment. The use of mainstream technologies, such as UML and XML means that design and content is available in robust form with widely available skill sets.
Assembling and managing public transport content models represents a significant long term investment for a Transport Operator Much of the data is inherently complex (e.g. timetables or fares) and is changing continuously. Accurate coherent data sets need to be created to integrate many different types of data and be kept up to date though many different workflows. NeTEx is concerned precisely with such a content model including the necessary metadata to manage it, and gives a long term strategic model for exchanging data between many different systems, one that is already ‘future proofed’ by the inclusion of many advanced features and additional functional modules.
A significant part of the lifetime expense of a system comes from maintenance and support to meet changing business needs. Whereas with modern web technologies new web services to request data can be constructed with relative ease, (e.g. adding new syntactic views as different APIS), changing the underlying data model is harder and must be managed in a distributed context – different systems will upgrade at different times, so multiple versions must be able to exist concurrently and without confusion. The NeTEx model is strictly versioned and designed to allow a managed evolution. Successive versions can easily be regression tested against existing XML documents to ensure compatibility and correctness.