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High-Level Orchestrator
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Introduction
==============
The aerOS High-level Orchestration part in the multi-level orchestration architecture is responsible for the 
smart placement of the services inside the federated domains taking into account the services requirements and 
the infrastructure constraints. Finally, it interacts with the Low-level Orchestrator to actually run the 
service in the selected IE.


HLO components
==============

Considering its complexity and the engagements of many partners in its development, the HLO has been decomposed into different components illustrated in the image below, following a microservices architecture.

.. toctree::
    :maxdepth: 1

    hlo_fe.rst
    aggregation_alert.rst
    allocation.rst
    deployment.rst


.. image:: ./hlo_components.png
  :alt: aerOS HLO architecture block
  :align: center