Right to use (RTU) is a license that controls the working mode of a Flex-PON port. The working mode of a Flex-PON port can be changed by using different RTUs.
When formulating an evolution solution for the Flex-PON, ensure that the port mode is supported by the RTU, optical module, and ONU. The following table lists the mapping between the Flex-PON port mode and the RTU, optical module, and ONU type.
|Port Mode||RTU Type||Optical Module Type||ONU Type|
|GPON||No need RTU||GPON||GPON ONU|
|XG-PON||10G PON RTU||XG-PON||XG-PON ONU|
|XGS-PON||10G PON RTU||XGS-PON||· XG-PON ONU
· XGS-PON ONU
|XG-PON/GPON Combo||10G PON RTU||XG-PON/GPON Combo||· GPON ONU
· XG-PON ONU
|XG-PON/GPON Combo||No RTU||XG-PON/GPON Combo||GPON ONU|
|XGS-PON/GPON Combo||10G PON RTU||XGS-PON/GPON Combo||· GPON ONU
· XG-PON ONU
· XGS-PON ONU
|XGS-PON/GPON Combo||No RTU||XGS-PON/GPON Combo||GPON ONU|
The process for NCE to authorize RTUs is as follows:
- NCE polls the total RTU consumption of all managed OLTs at a specified time every day.
- NCE notifies all OLTs of whether RTUs are sufficient based on the polling result:
- If the RTUs are sufficient, a message indicating that the RTUs are sufficient is sent to all OLTs.
- If the RTUs are overloaded (exhausted), the RTU overload information is sent to all OLTs.
- An OLT triggers RTU authorization in either of the following modes:
- Method 1: On the OLT, run the port flex-mode command to configure the Flex-PON port mode.
- Method 2: Insert an optical module into the Flex-PON port on the OLT.
- After the OLT triggers RTU authorization, the OLT determines whether to authorize the RTU based on the notification received from NCE (in step 2, NCE sends the RTU polling result to the OLT):
- If the RTU is sufficient, the RTU is granted to the Flex-PON port that requests authorization. In this case, the Flex-PON port can work normally in the target mode.
- If the RTU is overloaded (exhausted), the RTU is not granted to the Flex-PON port that requests authorization. In this case, the Flex-PON port cannot work in the target mode.
The below table describes the FAQs related to 10G PON RTU.
|What are the RTU types?||10G PON RTU on the Flex-PON board:
· Part number: 88035APW
· Description: 10G PON Port RTU, Based on per PON Port.
|Are RTUs managed at the port level?||Yes.|
|What are the symptoms of a Flex-PON port without an RTU enabled?||If the Flex-PON port of the RTU is disabled, the ONU cannot go online.
· The port works in GPON mode. When the optical module is XG(S)-PON/GPON Combo, only GPON ONUs can go online. XG(S)-PON ONUs are not allowed to go online.
· When the Flex-PON port works in XG(S)-PON/GPON mode and the optical module is XG(S)-PON/GPON Combo, only GPON ONUs can go online. XG(S)-PON ONUs are not allowed to go online.
|Will services be interrupted when the working mode of a Flex-PON port is switched?||· When a GPON optical module is deployed on a Flex-PON port, switch the Flex-PON port mode from GPON to XG(S)-PON/GPON Combo mode. The GPON ONU can go online regardless of whether RTUs are configured.
· When an XG(S)-PON/GPON Combo optical module is deployed on a Flex-PON port and the Flex-PON port mode is switched from GPON to XG(S)-PON/GPON Combo mode, the following situations occur:
§ If there is no RTU, the XG(S)-PON ONU cannot go online, but the GPON ONU goes online normally.
§ If there are RTUs, the XG(S)-PON ONU and GPON ONU can go online normally.
|After RTUs are activated for all ports on a Flex-PON board of an OLT, are RTUs unaware of the board migration if the board is migrated to another OLT?||RTUs are a part of Flex-PON boards. In the same NCE domain, RTUs can be migrated without being perceived by hardware boards. (After board migration, the number of RTUs consumed by the original OLT is deducted, and the number of RTUs consumed by the new OLT is increased.)|
|Is an RTU unaware of board replacement after a faulty Flex-PON board on an OLT is replaced?||· If the RTUs are overdrawn and the grace period expires, the customer needs to apply for a new RTU after replacing the board.
· If the RTUs are not used up or is overdrawn but within the grace period, the customer does not need to apply for an RTU after replacing the board. Instead, the original RTU license is used.
|On an OLT, after an XGS-PON optical module is migrated from Flex-PON board 1 to Flex-PON board 2, is the RTU unaware of the migration?||The RTU is a part of the Flex-PON board but not a part of the optical module. If only the optical module is migrated, the RTU is not migrated.|
|After a faulty OLT is replaced and the original OLT database is loaded, is the RTU unaware of the replacement?||RTUs are migrated with boards but not with OLTs. RTUs are unaware of OLT replacement.|
|If an OLT or Flex-PON board of a site is removed from the network, can the RTU be reclaimed to the NCE RTU resource pool?||· After a board exits from the network, the RTU used by the board is reclaimed.
· After an OLT is removed from the network (that is, the NE is deleted from NCE), the RTU used by the OLT is reclaimed. If a board on the OLT is used on another OLT, the number of used RTUs is re-calculated.
|After a Flex-PON port on an OLT is disabled and the board is removed, will the RTU be reclaimed to the RTU resource pool?||After a Flex-PON board is removed, the RTUs used by the board are reclaimed. After the board is re-inserted, the number of used RTUs is re-calculated.|
|Will RTU activation and management be affected when NCE is offline?||The status is the same as that before NCE goes offline.|
|Can an XGS-PON ONU Go Online Without an RTU?||If there is no 10G PON port RTU, the XGS-PON ONU is forced to go offline after going online, and the ONU goes offline because the port lacks RTU is reported.|