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GPON ONT STANDAR
5. Configuration
5.1 ONT activation
The ONT activation process has a distributed set of procedures that allow the connection of a inactive equipment to a PON network. This configu-
ration is done following the procedure described in the OMCI protocol.
5.2 Customization
For customization process, the requirements specified in the G.984.4, G.984.5 and ‘Implementer’s Guide’ in the G.984.4 v1 are taken into account.
5.2.1Software download from the OLT
The software download is made following the OMCI-based procedure included in the ‘Implementer’s Guide’ of the G.984.4 Recommendation.
The Managed Entity (ME) in charge of managing the software download is named Software Image. Per each ME containing independently-man-
ageable software, the ONT creates two software images. Each image will have three attributes:
Valid - if it has been verified that it’s content is an image with executable code;
Committed - if once the ONT is rebooted, it is loaded and executed;
Active - if it is loaded and it is being executed in the ONT.
There can be only one active image and only one commited image at a given moment. The ONT goes through a series of states in order to down-
load and activate a software image. Each state is defined according to the states of the variables of both images. The OLT controls the ONT state
through a series of commands:
Start download
It starts the software download sequence. This action is only valid for inactive and non-commited software images;
Download section
It downloads a section of a software image. This action is only valid for an image that is being downloaded;
End download
It indicates the end of a download sequence, providing the CRC and information about version for the final verification of the down-
loaded software image. This action is only valid for a software image that is being downloaded;
Activate image
It loads/executes a valid software image. When this action is applied to an inactive software image, the execution of the current code
image is suspended, the associated software image is loaded from the non-volatile memory and the execution of the new code
image is started. When this action is applied over a software image that is active, a reboot is executed;
Commit image
It selects a valid SW image to be loaded and executed by default when the ONT is restarted;
Composition of the Software Image
A software image is divided into sections of 31 bytes, with one section per OMCC message and each section protected by the CRC
of the OMCC. A group of sections makes up a window, and a group of windows constituting the image..