In multinational defense operations, either EU or NATO driven, the exchange of surveillance and reconnaissance data and information is an essential aspect to be able to act promptly. Coordinated processes and agreements are the basis, distribution architectures, services, interfaces and formats the prerequisite. In the NATO context, the Joint ISR (Intelligence, Surveillance and Reconnaissance) process supports the execution of surveillance and reconnaissance tasks. The Coalition Shared Data (CSD) concept and the associated specifications, interfaces and information models defined in STANAGs (Standardization Agreements), as well as the NATO ISR Interoperability Architecture (NIIA), facilitate the exchange of information based on the described processes. The EU uses CISE (Common Information Sharing Environment) and MARSUR (Maritime Surveillance), which are based on NATO-like principles. Within this frame, the OCEAN2020 (Open Cooperation for European mAritime awareNess) project, funded by the European Union's Preparatory Action on Defense Research and implemented by the European Defense Agency, sees 42 partners from 15 EU countries working to network future maritime surveillance and interdiction missions at sea integrating drones and unmanned submarines into fleet operations. Here data and information will be integrated in a comprehensive (maritime) picture of developing situations for military commanders on different unit levels. Maritime Operation Centers (MOC) on a national and EU level can be connected with operational commands/units to exchange information. With its remote-acting units equipped with only temporary and often narrow-band network connections, the Navy places particular demands on architecture (s). This paper focuses on the challenge to define flexible architectures for maritime operations.