Optical network terminal and a method therein for maintenance of the same

1. A method for maintenance and administration of an Optical Network Termination (ONT) comprised in an Optical Distribution Network (ODN), the method comprising:

connecting an Optical Line Termination (OLT) in the ODN to a maintenance unit comprised in the ONT in response to a first optical in-band signal being received from the OLT instructing the ONT to enter a maintenance mode;

updating existing maintenance and administration information in the maintenance unit, the maintenance and administration information relating to operation of the ONT when receiving new maintenance and administration information from the OLT;

connecting the OLT to a host connected to the ONT in response to at least one of:

receiving, from the OLT, a second optical in-band signal instructing the ONT to enter an operation mode, said operation mode being different from the maintenance mode;

expiration of a predetermined period of time;

operating the ONT in accordance with the updated maintenance and administration information in the maintenance unit;

wherein reception of the first optical in-band signal starts a maintenance timer;

wherein the ONT remains in the maintenance mode until the maintenance timer expires or the second optical in-band signal is received from the OLT instructing the ONT to enter the operation mode.

2. The method of claim 1 , wherein the first received optical in-band signal comprises a predetermined pattern of bits.

3. The method of claim 2 , wherein the predetermined pattern of bits comprises a predetermined number of consecutive zeroes corresponding to low optical intensity.

4. The method of claim 1 , wherein the first received optical in-band signal comprises a predetermined number of ones, corresponding to high optical intensity, causing saturation of the ONT to thereby trigger the ONT to enter the maintenance mode.

5. An Optical Network Termination (ONT) comprised in an Optical Distribution Network (ODN), the ONT comprising:

one or more processing circuits configured to function as:

a maintenance unit configured to control operation of the ONT;

a connecting module configured to connect an Optical Line Termination (OLT) in the ODN to the maintenance unit in response to a first optical in-band signal being received from the OLT instructing the ONT to enter a maintenance mode;

an updating module configured to update existing maintenance and administration information in the maintenance unit, the maintenance and administration information relating to the operation of the ONT when receiving new maintenance and administration information from the OLT;

wherein the connecting module further is configured to connect the OLT to a host connected to the ONT in response to at least one of:

receipt, from the OLT, of a second optical in-band signal instructing the ONT to enter an operation mode, said operation mode being different from the maintenance mode;

expiration of a predetermined period of time;

wherein the maintenance unit further is configured to operate the ONT in accordance with the updated maintenance and administration information in the maintenance unit; and

a timing circuit configured to start a maintenance timer in response to the ONT receiving the first optical in-band signal;

wherein the ONT is configured to remain in the maintenance mode until the maintenance timer expires or the second optical in-band signal is received from the OLT instructing the ONT to enter the operation mode;

wherein the connecting module is configured to connect the OLT to the host.

6. The ONT of claim 5 , wherein the first received optical in-band signal comprises a predetermined pattern of bits.

7. The ONT of claim 6 , wherein the predetermined pattern of bits comprises a predetermined number of consecutive zeroes, corresponding to low optical intensity.

8. The ONT of claim 5 , wherein the first received optical in-band signal comprises a predetermined number of ones, corresponding to high optical intensity, causing saturation of the ONT, wherein the ONT is configured to enter the maintenance mode in response to saturation of the ONT.