In the context of the Franco-German research project Re(h)strain, this work focuses on a global system analysis integrating both safety and security analysis of international and/or urban railway stations. The Re(h)strain project focuses on terrorist attacks on high speed train systems and investigates prevention and mitigation measures to reduce the overall vulnerability and strengthen the system resilience. One main criterion regarding public transport issues is the number of passengers. For example, the railway station of Paris 'Gare du Nord' deals with a bigger number of passengers than the biggest airport in the world (SNCF open Data 2014), the Atlanta airport, but in terms of passengers, it is only around the 23rd rank railway station in the world. Due to the enormous mass of people, this leads to the system approach of breaking out the station into several classes of zones, e.g. entrance, main hall, quays, trains, etc. All classes are analysed considering state-of-the-art parameters, like targets attractiveness, feasibility of attack, possible damage, possible mitigation and defences. Then, safety incidence of security defence is discussed in order to refine security requirement with regard to the considered zone. Finally, global requirements of security defence correlated to the corresponding class of zones are proposed. A case study based on the works in Re(h)strain is used as an illustration to demonstrate how the above-mentioned security and safety requirements may be implemented and handled at train stations. Therefore, the different security measures proposed for an unaffected flow of passengers are correlated to existing ones, such as video surveillance and security personal patrolling. The results of sensor set-ups realised within the project and tested in real environment show new ways of implementing innovative techniques to security applications. Depending on the technology, sensor portals at the entrances of train stations or sensor nodes distributed throughout the station increase the level of protection achievable for the detection of threats as part of preventive security concepts. The fusion of data gained by different sensor systems, including person-tracking by non-visual object recognition and trailing, enables a core function of a security assistance system. This assistance system makes security personnel aware of threats and the location of possible carriers of suspicious material as a prior condition to successful intervention measures. The high level of automation reduces human intervention to a minimum. In the conclusion it will be recommended to think of international railway stations as complex interconnected systems which are made for sharing traffic flows. It means that thinking about local solutions may produce safety problems to connected zones due to possible overcrowding.