Information Technology Reference
In-Depth Information
Fig. 10. Dual-Licensing concept providing a cost sharing scheme for financing new
functions (Add-on SW Modules) and improvements for those users who need it, by
keeping cost low for those not requiring enhanced functionality.
a scheduled release scheme (e.g. defining a fixed release day per year or any
other reasonable frequency), all new modules will be available only under the
For-Fee-License first, until R&D costs have been paid off by those users, who
want to make use of the new functionality, while all others can stick with the
older, but free of charge software versions.
Once the new features are paid off, those particular software modules can
then be set under the FLOSS license (EUPL). That allows fair cost sharing
for all early implementers and does not leave an undesired burden on those
users, who can live without the additional functions for a while, but still
being able to upgrade later on.
Since those upgrades will be provided by service level agreements through
OEMs or software service providers, customers have the choice to either opt
for low cost, but later upgrade service or higher priced early implementing
services, whatever fits best to their business needs.
The dual-licensing scheme has an additional advantage, allowing even
those ETCS suppliers, who are not able, due to technical limitations or legal
restrictions caused by their legacy system design or other reasons, to put
their software under an OSS license, never the less being able to participate
in the cost sharing effects for further add-on functional development. In most
cases it is technically much easier to implement a “small API”, interfacing
just for the add-on functions, rather than providing a fully functional API
for the whole kernel (figure 11).
If the non-OSS supplier wants to make use of those Add-on-SW-Modules
from the library, he cannot use the OSS-licensed software, but can combine
