The European initiative Shift2Rail (S2R) joins efforts for smart and sustainable growth in the railway sector by fostering research and innovation. Specifically, the project FR8RAIL within the Innovation Programme 5 (IP5) 'rail freight' of S2R aims to remove limiting factors of rail freight transportation. The work presented here is part of FR8RAIL and addresses the use and implementation of positioning strategies for rail freight transportation. Freight localization services based on on-board positioning, for example, can facilitate logistic optimization schemes that rely on continuous position and speed information. No extra trackside infrastructure is required, which reduces implementation and maintenance costs. The paper describes the challenges and requirements of on-board positioning strategies for the use in rail freight transportation and presents solution concepts (positioning requirements, hardware architecture, algorithms) for a more competitive rail freight