Abstract: Systems and methods of compensating for the delay asymmetry of coherent optical modems in a packet optical network include measuring fill levels of one or more queues each including an elastic First-In-First-Out (FIFO) circuit used in a transport mapping scheme, wherein the transport mapping scheme is one or more of client mapping to Optical Transport Unit (OTU) and OTU mapping to Flexible OTN (FlexO); and performing adjustments in a clock based in part on the measured fill levels, wherein the adjustments are configured to reduce a Time Error (TE) in the packet network based on delay asymmetry between two nodes.

Abstract: Systems and methods of compensating for the delay asymmetry of coherent optical modems in a packet optical network include measuring fill levels of one or more queues each including an elastic First-In-First-Out (FIFO) circuit used in a transport mapping scheme, wherein the transport mapping scheme is one or more of client mapping to Optical Transport Unit (OTU) and OTU mapping to Flexible OTN (FlexO); and performing adjustments in a clock based in part on the measured fill levels, wherein the adjustments are configured to reduce a Time Error (TE) in the packet network based on delay asymmetry between two nodes.

Abstract: Systems and methods for the relative phase measurement and alignment of 66B encoded signals include receiving a plurality of 66B encoded signals each comprising sync headers which are periodically converted, determining a phase of each of the plurality of 66B encoded signals based on the periodically converted sync headers, and aligning the phase of each of the plurality of 66B encoded signals based on the determining. The periodically converted sync headers can include changing one of a first bit and a second bit of the sync header. A period of the periodically converted sync header can be set at twice a phase difference which is compensated at an egress point of the plurality of 66B encoded signals.

Abstract: Systems and methods for the relative phase measurement and alignment of 66B encoded signals include receiving a plurality of 66B encoded signals each comprising sync headers which are periodically converted, determining a phase of each of the plurality of 66B encoded signals based on the periodically converted sync headers, and aligning the phase of each of the plurality of 66B encoded signals based on the determining. The periodically converted sync headers can include changing one of a first bit and a second bit of the sync header. A period of the periodically converted sync header can be set at twice a phase difference which is compensated at an egress point of the plurality of 66B encoded signals.

Abstract: A precision time transfer method, in a first node that communicates with a second node, to determine a difference in time between the first node and the second node, the precision time transfer method includes receiving a departure time, TD-A, from the second node, wherein the departure time is determined by the second node based on detecting a timing marker in a Forward Error Correction (FEC) frame or logical layer; determining an arrival time, TA-B, based on detecting the timing marker in the FEC frame; and determining a time difference based on the departure time and the arrival time wherein the timing marker is detected at a last point in a transmitter of the second node and at a first point in a receiver of the first node, during FEC processing.

Abstract: A precision time transfer method, in a first node that communicates with a second node, to determine a difference in time between the first node and the second node, the precision time transfer method includes receiving a departure time, TD-A, from the second node, wherein the departure time is determined by the second node based on detecting a timing marker in a Forward Error Correction (FEC) frame or logical layer; determining an arrival time, TA-B, based on detecting the timing marker in the FEC frame; and determining a time difference based on the departure time and the arrival time wherein the timing marker is detected at a last point in a transmitter of the second node and at a first point in a receiver of the first node, during FEC processing.