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NRP Backend Architecture
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.. todo:: Add author/responsible

Purpose
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The NRP Backend is responsible for providing a :ref:`backend-rest-api` to create and control experiment simulations. For each experiment simulation the :abbr:`CLE (Closed Loop Engine)` is started to run it. 

.. _architecture-overview:
.. image:: img/architecture_overview.png
   :width: 100%

   Overview of HBP SP10

:numref:`architecture-overview` shows the overview of the Neurorobotics subproject SP10 of the Human Brain Project (HBP). The NRP Backend provides a REST API to create and control experiment simulations.


Architecture of the NRP Backend
-------------------------------

.. _architecture-components:
.. image:: img/architecture_components_backend.png
   :width: 100%

   Architecture of NRP Backend with Frontend as context

:numref:`architecture-components` shows the architecture of the NRP Backend together with the Frontend as context. The REST API takes request 
from the Frontend and forwards them to the backend component related to a request. Creating a new simulation triggers the generation of a launch script for the CLE from the experiment configuration :class:`hbp_nrp_backend.exd_config`. This is done by modules :class:`hbp_nrp_backend.exd_config.experiment_configuration_script`. Requesting a state change triggers a transition between simulation states, see :doc:`simulation_states` for details. Requesting an interaction is directly forwarded to the Closed Loop Engine.

Details on the REST API can be found here: :doc:`REST-API`.