# US 2014/0208146 A1 · Time Protocol Latency Correction Based On Forward Error Correction Status > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0208146 A1 - Document ID: US20140208146A1 - Status: Published application - Kind: A1 - Application number: 13/744,704 - Filed: 2013-01-18 - Published: 2014-07-24 - Earliest claimed: 2013-01-18 - Assignees: Intel Corporation - Inventors: KENT LUSTED - Web page: https://patentgrep.com/patent/US20140208146A1 ## CPC - H04L 7/0037: {Delay of clock signal} - H04L 1/0009: {by adapting the channel coding (H04L1/1812 takes precedence)} - H04L 1/0072: {Error control for data other than payload data, e.g. control data} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract One embodiment provides a method for time protocol latency correction based on forward error correction (FEC) status. The method includes determining, by a network node element, if a forward error correction (FEC) decoding mode is enabled or disabled for a packet received from a link partner in communication with the network node element. The method also includes determining, by the network node element, a first time correction factor if an FEC decoding mode is enabled, the first time correction factor includes a time delay associated with the enabled FEC decoding mode and the first time correction factor is applied to a time stamp associated with the packet. The method also includes determining, by the network node element, a second time correction factor if an FEC decoding mode is disabled, the second time correction factor is applied to the time stamp associated with the packet. ## Claims ### Claim 1 A network node element, comprising: a network controller configured to communicate with a link partner using an Ethernet communications protocol; the network controller further configured to: determine if a forward error correction (FEC) decoding mode is enabled or disabled for a packet received from the link partner; determine a first time correction factor if an FEC decoding mode is enabled, the first time correction factor includes a time delay associated with the enabled FEC decoding mode and the first time correction factor is applied to a time stamp associated with the packet; and determine a second time correction factor if an FEC decoding mode is disabled, the second time correction factor is applied to the time stamp associated with the packet. ### Claim 2 (depends on 1) The network node element of claim 1, wherein the network controller is further configured to determine at least one channel quality parameter of at least one channel of a communication link between the network controller and the link partner; and determine whether to enable or disable the FEC decoding mode for use by the network node element based on, at least in part, the at least one channel quality parameter. ### Claim 3 (depends on 2) The network node element of claim 2, wherein the channel quality parameter is selected from the group of a bit error rate (BER), signal-to-noise ratio (SNR), cross talk, environmental noise, linearity or impulse response. ### Claim 4 (depends on 1) The network node element of claim 1, wherein the network controller is further configured to determine if the packet received from the link partner is encoded, by the link partner, using at least one forward error correction (FEC) mode. ### Claim 5 (depends on 1) The network node element of claim 1, wherein the network controller comprises physical interface (PHY) circuitry, and wherein the first and second time correction factors are based on, at least in part, a delay caused by processing of the packet by the PHY circuitry. ### Claim 6 (depends on 1) The network node element of claim 1, further comprising a local clock, wherein the time stamp is based on a time value of the local clock plus the first or second time correction factor. ### Claim 7 A method for time protocol latency correction based on forward error correction (FEC) status, comprising: determining, by a network node element, if a forward error correction (FEC) decoding mode is enabled or disabled for a packet received from a link partner in communication with the network node element; determining, by the network node element, a first time correction factor if an FEC decoding mode is enabled, the first time correction factor includes a time delay associated with the enabled FEC decoding mode and the first time correction factor is applied to a time stamp associated with the packet; and determining, by the network node element, a second time correction factor if an FEC decoding mode is disabled, the second time correction factor is applied to the time stamp associated with the packet. ### Claim 8 (depends on 7) The method of claim 7, further comprising: determining at least one channel quality parameter of at least one channel of a communication link between the network controller and the link partner; and determining whether to enable or disable the FEC decoding mode for use by the network node element based on, at least in part, the at least one channel quality parameter. ### Claim 9 (depends on 8) The method of claim 8, wherein the channel quality parameter is selected from the group of a bit error rate (BER), signal-to-noise ratio (SNR), cross talk, environmental noise, linearity or impulse response. ### Claim 10 (depends on 7) The method of claim 7, further comprising: determining if the packet received from the link partner is encoded, by the link partner, using at least one forward error correction (FEC) mode. ### Claim 11 (depends on 7) The method of claim 7, wherein the network node element comprises physical interface (PHY) circuitry, and wherein the first and second time correction factors are based on, at least in part, a delay caused by processing of the packet by the PHY circuitry. ### Claim 12 (depends on 7) The method of claim 7, wherein the network node element comprises a local clock, wherein the time stamp is based on a time value of the local clock plus the first or second time correction factor. ### Claim 13 A system comprising, one or more tangible, non-transitory storage mediums having stored thereon, individually or in combination, instructions that when executed by one or more processors result in the following operations comprising: determine if a forward error correction (FEC) decoding mode is enabled or disabled for a packet received from a link partner in communication with a network node element; determine a first time correction factor if an FEC decoding mode is enabled, the first time correction factor includes a time delay associated with the enabled FEC decoding mode and the first time correction factor is applied to a time stamp associated with the packet; and determine a second time correction factor if an FEC decoding mode is disabled, the second time correction factor is applied to the time stamp associated with the packet. ### Claim 14 (depends on 13) The system of claim 13, wherein the instructions that when executed by one or more processors results in the following additional operations comprising determine at least one channel quality parameter of at least one channel of a communication link between the network controller and the link partner; and determine whether to enable or disable the FEC decoding mode for use by the network node element based on, at least in part, the at least one channel quality parameter. ### Claim 15 (depends on 14) The system of claim 14, wherein the channel quality parameter is selected from the group of a bit error rate (BER), signal-to-noise ratio (SNR), cross talk, environmental noise, linearity or impulse response. ### Claim 16 (depends on 13) The system of claim 13, wherein the instructions that when executed by one or more processors results in the following additional operations comprising determine if the packet received from the link partner is encoded, by the link partner, using at least one forward error correction (FEC) mode. ### Claim 17 (depends on 13) The system of claim 13, wherein the instructions that when executed by one or more processors results in the following additional operations comprising determine a delay time caused by processing of the packet by physical interface (PHY) circuitry associated with the network node element; and wherein the first and second time correction factors are based on, at least in part, a delay caused by processing of the packet by the PHY circuitry. ### Claim 18 (depends on 23) The system of claim 23, wherein the instructions that when executed by one or more processors results in the following additional operations comprising determine a time value of a local clock associated with the network node element; and wherein the time stamp is based on a time value of the local clock plus the first or second time correction factor. ### Claim 19 A network node element, comprising: a network interface card configured to be coupled to a bus, the network interface card is configured to communicate with a link partner using an Ethernet communications protocol; the network interface card is further configured to: determine if a forward error correction (FEC) decoding mode is enabled or disabled for a packet received from the link partner; determine a first time correction factor if an FEC decoding mode is enabled, the first time correction factor includes a time delay associated with the enabled FEC decoding mode and the first time correction factor is applied to a time stamp associated with the packet; and determine a second time correction factor if an FEC decoding mode is disabled, the second time correction factor is applied to the time stamp associated with the packet. ### Claim 20 (depends on 19) The network node element of claim 19, wherein the network interface card is further configured to determine at least one channel quality parameter of at least one channel of a communication link between the network controller and the link partner; and determine whether to enable or disable the FEC decoding mode for use by the network node element based on, at least in part, the at least one channel quality parameter. ### Claim 21 (depends on 20) The network node element of claim 20, wherein the channel quality parameter is selected from the group of a bit error rate (BER), signal-to-noise ratio (SNR), cross talk, environmental noise, linearity or impulse response. ### Claim 22 (depends on 19) The network node element of claim 19, wherein the network interface card is further configured to determine if the packet received from the link partner is encoded, by the link partner, using at least one forward error correction (FEC) mode. ### Claim 23 (depends on 19) The network node element of claim 19, wherein the network interface card comprises physical interface (PHY) circuitry, and wherein the first and second time correction factors are based on, at least in part, a delay caused by processing of the packet by the PHY circuitry. ### Claim 24 (depends on 19) The network node element of claim 19, further comprising a local clock, wherein the time stamp is based on a time value of the local clock plus the first or second time correction factor. ### Claim 25 A computer-readable program product comprising, one or more tangible, non-transitory storage mediums having stored thereon, individually or in combination, hardware descriptive language instructions that, when executed by one or more processors, specifies circuitry that is configured to perform the following operations comprising: determine if a forward error correction (FEC) decoding mode is enabled or disabled for a packet received from a link partner in communication with a network node element; determine a first time correction factor if an FEC decoding mode is enabled, the first time correction factor includes a time delay associated with the enabled FEC decoding mode and the first time correction factor is applied to a time stamp associated with the packet; and determine a second time correction factor if an FEC decoding mode is disabled, the second time correction factor is applied to the time stamp associated with the packet. ### Claim 26 (depends on 25) The computer-readable program product of claim 25, wherein the instructions that when executed by one or more processors specifies circuitry that is configured to perform the following additional operations comprising: determine at least one channel quality parameter of at least one channel of a communication link between the network controller and the link partner; and determine whether to enable or disable the FEC decoding mode for use by the network node element based on, at least in part, the at least one channel quality parameter. ### Claim 27 (depends on 26) The computer-readable program product of claim 26, wherein the channel quality parameter is selected from the group of a bit error rate (BER), signal-to-noise ratio (SNR), cross talk, environmental noise, linearity or impulse response. ### Claim 28 (depends on 25) The computer-readable program product of claim 25, wherein the instructions that when executed by one or more processors specifies circuitry that is configured to perform the following additional operations comprising: determine if the packet received from the link partner is encoded, by the link partner, using at least one forward error correction (FEC) mode. ### Claim 29 (depends on 25) The computer-readable program product of claim 25, wherein the instructions that when executed by one or more processors specifies circuitry that is configured to perform the following additional operations comprising: determine a delay time caused by processing of the packet by physical interface (PHY) circuitry associated with the network node element; and wherein the first and second time correction factors are based on, at least in part, a delay caused by processing of the packet by the PHY circuitry. ### Claim 30 (depends on 23) The computer-readable program product of claim 23, wherein the instructions that when executed by one or more processors specifies circuitry that is configured to perform the following additional operations comprising: determine a time value of a local clock associated with the network node element; and wherein the time stamp is based on a time value of the local clock plus the first or second time correction factor.