An ambition of the iFishIENCi project is to provide to the market a flexible iFishIENCi Biology Online Steering System (iBOSS) that significantly improves production control and management for all fish aquaculture systems. iBOSS intends to maximise feed utilisation through smart feeding, providing continuous monitoring of fish behaviour, health and welfare and reducing response times to aberrations. In addition, iFishIENCi targets circular principles and zero waste by qualifying new and sustainable organic value chains for feeds, and valorisation of by-products. The iBOSS system is a central piece of the iFishIENCi project and also allows to connect information from the Fish-Talk-to-Me project innovation which integrates conventional and emerging technologies for enabling continuous control on fish behaviour, growth, physiology, welfare, health & environmental microbiome The present deliverable “D2.2 IoT open architecture and new elements specifications” is the first technical contribution of the project and ambitions to provide the baseline for following technical development in the project. It this includes: • A description of the foreseen innovations, in particular concerning sensing of water and fish related parameters (Fish-Talk-to-Me) (section 2) • A list of platform requirements extracted from the pilot sites description and building upon the market knowledge of the consortium partners (section 3) • A proposal of a plan for data modelling, allowing interoperable exchange of information among the different project components (human and IT) (section 4) • Finally, a concrete technical plan is proposed with a proposal for interfaces protocol (section 5) architecture analysis (section 6), as well as a plan for integration of the components building upon the planned experiments in the development sites (section 7).