Service oriented computing and peer-to-peer (P2P) computing are emerging technologies which provide, from the architectural point of view, scalability and flexibility. From their properties both architectures are quite similar, e.g. in both architectures nobody has a complete system overview and no central administration exists. Besides other challenges, this leads to the question how data can be stored in a reliable way in the P2P and service oriented environments. In this paper we analyze and discuss the requirements as well as the challenges and give an outlook on our research activities which address the identified problems.