What Is The XGS-PON ONU State Mean?

ONU state definition
ONU activation process

ONU state definition

The seven states of the xgs-pon ONU are defined as:
(1) O1: initial state;
(2) O2~3: sequence number state;
(3) O4: ranging state;
(4) O5: operation state;
(5) O6: intermittent downlink frame synchronization loss state;
(6) O7: emergency stop state;
The specific definition of each state and the state transfer mode are according to the provisions of YD/T 3691.3-2020

ONU activation process

The OLT shall support legitimacy authentication of the ONU based on the serial number (SN) method, based on the password, SN+Password, and logical ONU ID method (LOID).
Among them, the Password authentication method adopts the Registration_ID field (hereinafter referred to as Registration ID) in the Registration message to carry the authentication information, and the effective length of the authentication information carried by the Registration_ID shall be specifiable.
Sequence number authentication method, Password authentication method and (SN+Password) authentication method are realized through TC layer activation process; LOID authentication is realized through OMCI interaction.

When the OLT authenticates the legality of the ONU based on the SN (serial number), the activation process of the ONU is shown in Figure 5. when the OLT checks the received SN of the ONU and considers that the ONU is not legal, it sends a Disable_Serial_Number (Disable) message to the ONU that reported the serial number to notify that the ONU enters the Emergency Stop State (O7). After reconfiguring the SN on the network management side, if the OLT recognizes that the ONU that was previously judged as illegal and entered the O7 state becomes a legal ONU, the OLT sends a Disable_Serial_Number (Enable) message to the ONU to notify it to enter the serial number state (O2-O3). The Registration ID message can be ignored or filled with all zeros in this flow.