# US 11,309,984 B2 · TCM control for physical layer on OTU ports > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,309,984 B2 - Document ID: US11309984B2 - Status: Granted - Kind: B2 - Application number: 16/808,464 - Filed: 2020-03-04 - Published: 2021-09-09 - Granted: 2022-04-19 - Earliest claimed: 2020-03-04 - Assignees: Ciena Corporation - Applicants: Ciena Corporation - Inventors: Trevor John Ibach; Larry Babineau; Trevor Donald Corkum - Web page: https://patentgrep.com/patent/US11309984B2 ## CPC - H04J 3/1652: {Optical Transport Network [OTN]} - H04J 3/14: Monitoring arrangements {(for SDH/SONET rings H04J3/085)} - H04J 2203/0051: Network Node Interface, e.g. tandem connections, transit switching - 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) ## Abstract Systems and methods for Tandem Connection Monitor (TCM) control for the physical layer on Optical Transport Unit (OTU) ports provide the ability of the TCM status to directly control client laser state (on/off) so that protection engines and coordination between modules is not required. The systems and methods include receiving a specific defect such as a Tandem Connection Monitor (TCM) defect or a Server Signal Fail (SSF) defect from interface circuitry; propagating the TCM defect or the SSF defect from the interface circuitry to an interface associated with a modem including a physical port connected to a network; and selectively disabling a laser in the modem based on the specific defect, e.g., the TCM defect or the SSF defect from the interface circuitry. ## Claims ### Claim 1 A network element comprising: a modem including a physical port connected to a network, wherein the network includes Optical Transport Network (OTN); processing circuitry communicatively coupled to the modem for implementing a plurality of OTN-related functions; interface circuitry communicatively coupled to the processing circuitry; and an interface in the processing circuitry configured to detect a specific defect from the interface circuitry, wherein the interface is connected to the modem and the modem is configured to selectively disable a laser based on the specific defect from the interface circuitry, and wherein the processing circuitry includes an Optical Channel Data Unit level k (ODUk) TCM x function (x=1 to 6) connected to the interface circuitry, and the specific defect includes one of a Tandem Connection Monitor (TCM) defect and a Server Signal Fail (SSF) defect, wherein the ODUk TCM x function is configured to propagate an Alarm Indication Signal (AIS) towards the modem, responsive to the specific defect from the interface circuity, in addition to causing the laser to be disabled. ### Claim 2 (depends on 1) The network element of claim 1, wherein the ODUk TCM x function is configured to receive the specific defect from the interface circuitry and provide the specific defect to the modem. ### Claim 3 (depends on 1) The network element of claim 1, wherein the ODUk TCM x function is configured to receive the specific defect from the interface circuitry, and provide the specific defect to a laser control function that is connected to the modem. ### Claim 4 (depends on 1) The network element of claim 1, wherein the processing circuitry further includes an Optical Transport Function level k (OTUk) function between the ODUk TCM x function and the modem, wherein the interface is through the OTUk function. ### Claim 5 (depends on 1) The network element of claim 1, wherein the interface includes software monitoring of the specific defect from the interface circuitry and explicitly controlling the laser based thereon. ### Claim 6 (depends on 1) The network element of claim 1, wherein the interface includes a hardware-based connection connecting a signal of the specific defect from the interface circuitry to laser control. ### Claim 7 A method comprising: receiving a specific defect from interface circuitry; propagating the specific defect from the interface circuitry to an interface associated with a modem including a physical port connected to a network, wherein the network includes Optical Transport Network (OTN), and wherein the propagating is via processing circuitry that includes an Optical Channel Data Unit level k (ODUk) TCM x function (x=1 to 6) connected to the interface circuitry, and the specific defect is one of a Tandem Connection Monitor (TCM) defect and a Server Signal Fail (SSF) defect; and selectively disabling a laser in the modem based on the specific defect from the interface circuitry, wherein the ODUk TCM x function is configured to propagate an Alarm Indication Signal (AIS) towards the modem, responsive to the specific defect from the interface circuitry, in addition to causing the laser to be disabled. ### Claim 8 (depends on 7) The method of claim 7, wherein the ODUk TCM x function is configured to receive the TCM defect or the SSF defect from the interface circuitry and provide the specific defect to the modem. ### Claim 9 (depends on 7) The method of claim 7, wherein the ODUk TCM x function is configured to receive the specific defect from the interface circuitry, and provide the specific defect to a laser control function that is connected to the modem. ### Claim 10 A network element comprising: a modem including a physical port connected to a network, wherein the network includes Optical Transport Network (OTN); processing circuitry communicatively coupled to the modem for implementing a plurality of OTN-related functions; interface circuitry communicatively coupled to the processing circuitry; and an interface in the processing circuitry configured to detect a specific defect from the interface circuitry, wherein the interface is connected to the modem and the modem is configured to selectively disable a laser based on the specific defect from the interface circuitry, and wherein the processing circuitry includes an Optical Channel Data Unit level k (ODUk) TCM x function (x=1 to 6) connected to the interface circuitry, and the specific defect includes one of a Tandem Connection Monitor (TCM) defect and a Server Signal Fail (SSF) defect, wherein the processing circuitry further includes an Optical Transport Function level k (OTUk) function between the ODUk TCM x function and the modem, wherein the interface is through the OTUk function. ### Claim 11 (depends on 10) The network element of claim 10, wherein the ODUk TCM x function is configured to receive the specific defect from the interface circuitry and provide the specific defect to the modem. ### Claim 12 (depends on 10) The network element of claim 10, wherein the ODUk TCM x function is configured to receive the specific defect from the interface circuitry, and provide the specific defect to a laser control function that is connected to the modem. ### Claim 13 (depends on 10) The network element of claim 10, wherein the ODUk TCM x function is configured to propagate an Alarm Indication Signal (AIS) towards the modem, responsive to the specific defect from the interface circuitry, in addition to causing the laser to be disabled. ### Claim 14 (depends on 10) The network element of claim 10, wherein the interface includes software monitoring of the specific defect from the interface circuitry and explicitly controlling the laser based thereon. ### Claim 15 (depends on 10) The network element of claim 10, wherein the interface includes a hardware-based connection connecting a signal of the specific defect from the interface circuitry to laser control.