Rogue optical network interface device detection
View Patent ↗Techniques are described for identifying a rogue network interface device whose laser is not under control of a controller of the network interface device. The techniques identify the rogue network interface device based on reception of a predefined data pattern in a timeslot that is not reserved for any of the network interface devices without needing to disable upstream data transmission from the network interface devices during their assigned timeslots. The techniques also relate to a network interface device determining whether the network interface device is transmitting optical signals at a wavelength different than the wavelength that the OLT to which the network interface device is associated receives.
1. A method comprising:
receiving, with a network interface device, one or more requests from an optical line terminal (OLT) to determine whether the network interface device transmitted one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
determining, with the network interface device, that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
determining that the network interface device is transmitting the one or more optical signals at a wavelength that the OLT does not receive based on the determination that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission, and the reception of the one or more requests from the OLT; and
disabling the network interface device from transmitting upstream optical signals based on the determination that the network interface device is transmitting the one or more optical signals at the wavelength that the OLT does not receive.
2. The method of claim 1 , further comprising:
monitoring an optical output power level of a laser coupled to the network interface device during one or more of the timeslots assigned to the network interface device for upstream transmission,
wherein determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission comprises determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission based on the monitoring of the optical output power level.
3. The method of claim 1 , further comprising:
storing information indicating when the network interface device transmitted the one or more optical signals,
wherein determining that the network interface device transmitted the one or more optical signals during the one or more timeslots assigned to the network interface device for upstream transmission comprises determining that the network interface device transmitted the one or more optical signals during the one or more timeslots assigned to the network interface device for upstream transmission based on the stored information.
4. The method of claim 1 , wherein determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission comprises determining that the network interface device transmitted an optical signal for a timeslot of the timeslots following the reception of the request from the OLT.
5. The method of claim 1 ,
wherein receiving the one or more requests comprises receiving a plurality of requests from the OLT,
wherein determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission comprises determining that the network interface device transmitted the one or more optical signals during a plurality of timeslots assigned to the network interface device for upstream transmission, and
wherein determining that the network interface device is transmitting the one or more optical signals at a wavelength that the OLT does not receive comprises determining that the network interface device is transmitting the one or more optical signals at a wavelength that the OLT does not receive based on the determination that the network interface device transmitted the plurality of optical signals during one or more timeslots assigned to the network interface device for upstream transmission, and the reception of the plurality of requests from the OLT.
6. A network interface device comprising:
a laser; and
a controller configured to:
receive one or more requests from an optical line terminal (OLT) to determine whether the laser transmitted one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
determine that the laser transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
determine that the laser is transmitting the one or more optical signals at a wavelength that the OLT does not receive based on the determination that the laser transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission, and the reception of the one or more requests from the OLT; and
disable the network interface device from transmitting upstream optical signals based on the determination that the laser is transmitting the one or more optical signals at the wavelength that the OLT does not receive.
7. The network interface device of claim 6 , further comprising:
a monitor unit configured to monitor an optical output power level of the laser during one or more of the timeslots assigned to the network interface device for upstream transmission, and transmit information indicating the optical output power level to the controller,
wherein to determine that the laser transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission, the controller is configured to determine that the laser transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission based on the optical power level transmitted by the monitor unit.
8. The network interface device of claim 6 , further comprising:
a memory configured to store information indicating when the laser transmitted the one or more optical signals,
wherein to determine that the laser transmitted the one or more optical signals during the one or more timeslots assigned to the network interface device for upstream transmission, the controller is configured to determine that the laser transmitted the one or more optical signals during the one or more timeslots assigned to the network interface device for upstream transmission based on the stored information.
9. The network interface device of claim 6 , wherein to determine that the laser transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission, the controller is configured to determine that the laser transmitted an optical signal for a timeslot of the timeslots following the reception of the request from the OLT.
10. The network interface device of claim 6 ,
wherein to receive the one or more requests, the controller is configured to receive a plurality of requests from the OLT,
wherein to determine that the laser transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission, the controller is configured to determine that the laser transmitted the one or more optical signals during a plurality of timeslots assigned to the network interface device for upstream transmission, and
wherein to determine that the laser is transmitting the one or more optical signals at a wavelength that the OLT does not receive, the controller is configured to determine that the laser is transmitting the one or more optical signals at a wavelength that the OLT does not receive based on the determination that the laser transmitted the plurality of optical signals during one or more timeslots assigned to the network interface device for upstream transmission, and the reception of the plurality of requests from the OLT.
11. A network interface device comprising:
means for receiving one or more requests from an optical line terminal (OLT) to determine whether the network interface device transmitted one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
means for determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
means for determining that the network interface device is transmitting the one or more optical signals at a wavelength that the OLT does not receive based on the determination that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission, and the reception of the one or more requests from the OLT; and
means for disabling the network interface device from transmitting upstream optical signals based on the determination that the network interface device is transmitting the one or more optical signals at the wavelength that the OLT does not receive.
12. The network interface device of claim 11 , further comprising:
means for monitoring an optical output power level of a laser coupled to the network interface device during one or more of the timeslots assigned to the network interface device for upstream transmission,
wherein the means for determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission comprises means for determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission based on the monitoring of the optical output power level.
13. The network interface device of claim 11 , further comprising:
means for storing information indicating when the network interface device transmitted the one or more optical signals,
wherein the means for determining that the network interface device transmitted the one or more optical signals during the one or more timeslots assigned to the network interface device for upstream transmission comprises means for determining that the network interface device transmitted the one or more optical signals during the one or more timeslots assigned to the network interface device for upstream transmission based on the stored information.
14. The network interface device of claim 11 , wherein the means for determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission comprises means for determining that the network interface device transmitted an optical signal for a timeslot of the timeslots following the reception of the request from the OLT.
15. The network interface device of claim 11 ,
wherein the means for receiving the one or more requests comprises means for receiving a plurality of requests from the OLT,
wherein the means for determining that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission comprises means for determining that the network interface device transmitted the one or more optical signals during a plurality of timeslots assigned to the network interface device for upstream transmission, and
wherein the means for determining that the network interface device is transmitting the one or more optical signals at a wavelength that the OLT does not receive comprises means for determining that the network interface device is transmitting the one or more optical signals at a wavelength that the OLT does not receive based on the determination that the network interface device transmitted the plurality of optical signals during one or more timeslots assigned to the network interface device for upstream transmission, and the reception of the plurality of requests from the OLT.
16. A computer-readable storage medium having instructions stored thereon that when executed cause a controller of a network interface device to:
receive one or more requests from an optical line terminal (OLT) to determine whether the network interface device transmitted one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
determine that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission;
determine that the network interface device is transmitting the one or more optical signals at a wavelength that the OLT does not receive based on the determination that the network interface device transmitted the one or more optical signals during one or more timeslots assigned to the network interface device for upstream transmission, and the reception of the one or more requests from the OLT; and
disable the network interface device from transmitting upstream optical signals based on the determination that the network interface device is transmitting the one or more optical signals at the wavelength that the OLT does not receive.