====================== Reference Architecture ====================== This section describes the reference architecture, the function blocks, and the function entities of Escalator for the reader to well understand how the basic functions to be organized. The software stack on each node is generally as shown in the table below. .. figure:: images/figure2.png :name: figure2 :width: 100% Since the upgrading of control node will not affect the VNFs service in the blue box, this chapter will focusing on the upgrading of compute nodes. Precondition of Upgrade ======================= Upgrade related modules in VIM ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Upgrade operations are initiated by the user through the VIM. For VIM, upgrade management mainly contains the object: - **Upgrade Manager** Mainly responsible for control of the upgrade process.The Escalator is required to know the software deployment information of the platform and will use these information during the upgrading. It will be collected from some place, such as the Installer, Deploy Manager and Escalator itself, etc. - **VIM Interface**: Mainly responsible for the external interface, include Vi-Vnfm, Or-Vi. This module stores VNFO and VNFM external information such as address and authentication. - **Cloud Manager**: Mainly responsible for virtualization resources management,which might be considered made up of Openstack and SDN control node. - **System Support**: This layer is the runtime support environment of upper layers, e.g. Cloud Manager and VIM interface., including:OS, HA, etc. To upgrade the upper software is based on this module. .. figure:: images/figure3.png :name: figure3 :width: 100% .. Revision: 9ba9270d8373d6d4bb3d34ae6c618e9b5f937d63 Build date: 2016-05-28