# US 11,444,719 B2 · Virtualized sections for sectional control of optical links > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,719 B2 - Document ID: US11444719B2 - Status: Granted - Kind: B2 - Application number: 17/365,463 - Filed: 2021-07-01 - Published: 2021-10-21 - Granted: 2022-09-13 - Earliest claimed: 2017-09-29 - Assignees: Ciena Corporation - Applicants: Ciena Corporation - Inventors: Choudhury A. Al Sayeed; Mark Hinds - Web page: https://patentgrep.com/patent/US11444719B2 ## CPC - H04J 14/0287: {Protection in WDM systems} - H04J 14/0201: {Add-and-drop multiplexing} - H04B 10/07955: {Monitoring or measuring power} - H04J 2203/006: Fault tolerance and recovery - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) - H04B: TRANSMISSION ## Abstract Systems and methods include receiving first power snapshot from a receiving end of a foreign controlled link of the one or more foreign controlled optical links when there are no faults thereon; responsive to obtaining second power snapshot from the receiving end of the foreign controlled link, detecting a fault on one of at least one channel and part of the spectrum traversing the foreign controlled link; correlating the second power snapshot with the first power snapshots; and raising an indication of fault for the foreign controlled link based on the correlating. ## Claims ### Claim 1 A method of controlling one or more foreign controlled optical links comprising: receiving a first power snapshot from a receiving end of a foreign controlled link of the one or more foreign controlled optical links when there are no faults thereon; receiving a second power snapshot from the receiving end of the foreign controlled link; correlating the second power snapshot with the first power snapshot; and raising an indication of fault for one of at least one channel and part of the spectrum traversing the foreign controlled link based on the correlating. ### Claim 2 (depends on 1) The method of claim 1, further comprising displaying any of the first power snapshot and the second power snapshot for the receiving end. ### Claim 3 (depends on 1) The method of claim 1, wherein the correlating measures a power difference between the first power snapshot and the second power snapshot, and the fault alarm is based on the power difference being above a threshold. ### Claim 4 (depends on 1) The method of claim 1, wherein the fault is in any of a Loss of Frame (LOF), a Loss of Signal (LOS), and a Loss of Clock (LOC) detected on the at least one channel. ### Claim 5 (depends on 1) The method of claim 1, wherein the foreign controlled link is one of a submarine link and a terrestrial link. ### Claim 6 An apparatus comprising: a processor and memory storing instructions that, when executed, cause the processor to receive a first power snapshot from a receiving end of a foreign controlled link of the one or more foreign controlled optical links when there are no faults thereon, receive a second power snapshot from the receiving end of the foreign controlled link, correlate the second power snapshot with the first power snapshot; and raise an indication of fault for one of at least one channel and part of the spectrum traversing the foreign controlled link based on the correlating. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the instructions that, when executed, further cause the processor to display any of the first power snapshot and the second power snapshot for the receiving end. ### Claim 8 (depends on 6) The apparatus of claim 6, wherein the correlating measures a power difference between the first power snapshot and the second power snapshot, and the fault alarm is based on the power difference being above a threshold. ### Claim 9 (depends on 6) The apparatus of claim 6, wherein the fault is in any of a Loss of Frame (LOF), a Loss of Signal (LOS), and a Loss of Clock (LOC) detected on the at least one channel. ### Claim 10 (depends on 6) The apparatus of claim 6, wherein the foreign controlled link is one of a submarine link and a terrestrial link. ### Claim 11 A non-transitory computer-readable storage medium having computer readable code stored thereon for programming a device to perform steps of: receiving a first power snapshot from a receiving end of a foreign controlled link of the one or more foreign controlled optical links when there are no faults thereon; receiving a second power snapshot from the receiving end of the foreign controlled link; correlating the second power snapshot with the first power snapshot; and raising an indication of fault for one of at least one channel and part of the spectrum traversing the foreign controlled link based on the correlating. ### Claim 12 (depends on 11) The non-transitory computer-readable storage medium of claim 11, wherein the steps further include displaying any of the first power snapshot and the second power snapshot for the receiving end. ### Claim 13 (depends on 11) The non-transitory computer-readable storage medium of claim 11, wherein the correlating measures a power difference between the first power snapshot and the second power snapshot, and the fault alarm is based on the power difference being above a threshold. ### Claim 14 (depends on 11) The non-transitory computer-readable storage medium of claim 11, wherein the fault is in any of a Loss of Frame (LOF), a Loss of Signal (LOS), and a Loss of Clock (LOC) detected on the at least one channel.