Abstract: Implementing a distributed boundary clock in situations where book-end devices such as microwave TX/RX pairs must collaborate in achieving PTP on-path support is described. A dedicated channel, generally low-speed compared to the main channel is used to transfer timing from the master side to the slave side using framing and super-framing applied to the digital channel. Time-stamps of events such as super-frame boundaries are communicated between the two sides to enable timing transfer.

Abstract: A Managed Timing Engine (MTE) provides a primary timing output synchronized to a selected input reference from a multiplicity of input references. Additional timing outputs can be generated such that there is a programmable frequency offset (in ppb) between them and the main output. The rate (in Hz) of the outputs can be programmable. The MTE can introduce a programmable delay for periodic phase references.

Abstract: Implementing a distributed boundary clock in situations where book-end devices such as microwave TX/RX pairs must collaborate in achieving PTP on-path support is described. A dedicated channel, generally low-speed compared to the main channel is used to transfer timing from the master side to the slave side using framing and super-framing applied to the digital channel. Time-stamps of events such as super-frame boundaries are communicated between the two sides to enable timing transfer.

Abstract: Systems and methods are disclosed for utilizing slave (receive) time-stamp clock rates that are different from master (sender) time-stamp clock rates to randomize and thereby reduce systematic time-stamp granularity errors in the communication of network packets. The slave (receive) time-stamp clock rate for some embodiments is set to be a fixed value that has a relationship with the master (sender) time-stamp clock rate such that the ratio of the slave (receive) clock rate to the master (sender) clock rate is a rational number. Other embodiments use a time-varying frequency for the slave (receive) time-stamp clock rate to randomize the slave (receive) time-stamp clock with respect to the master (sender) time-stamp clock. Additional time-stamps can also be generated using a slave (receive) time-stamp clock having a rate set to equal the rate of the master (sender) time-stamp clock signal.

Abstract: A packet network that includes the distribution of timing information (time and frequency) between server and client devices can continue to operate in a holdover mode even when the server loses its primary timing reference based on GNSS. This is achieved by populating the packet network with some client devices that also have access to the same timing reference. These devices are used in a reverse timing transfer mode to provide a hack-up reference to the server and thereby provide a graceful solution to the problem of loss of reference.

Abstract: A method for implementing a distributed boundary clock in situations where book-end devices such as microwave TX/RX pairs must collaborate in achieving PTP on-path support is described. A dedicated channel, generally low-speed compared to the main channel is used to transfer timing from the master side to the slave side using framing and super-framing applied to the digital channel. Time-stamps of events such as super-frame boundaries are communicated between the two sides to enable timing transfer.

Abstract: Systems and methods are disclosed for direct passive monitoring of packet delay variation and time error in network packet communications. Packets traversing between slave and master clocks are monitored to provide direct results of the actual conditions without the need to rely upon inference determinations. Certain embodiments provide tap configurations to monitor packet flows, while certain other embodiments provide in-line configurations to monitor packet flows. Certain further embodiments provide multiple monitoring devices that can be used for passive monitoring purposes, such as passive monitoring to test boundary clock. These multiple monitoring devices can be configured to be within a single or different test instruments. Other variations are also described.

Abstract: A master and slave module are described that facilitate the distribution of timing, both frequency and phase over a radio link The signal transmitted from the master to the slave is suitable for delivering a frequency reference and an approximate phase/time. The precise phase at the slave is obtained by using a reverse communication between the slave and the master over the same radio channel in a time-division-duplex mode. Additional slaves can be accommodated by using a multiple time-slot arrangement.

Abstract: A master and slave module are described that facilitate the distribution of timing, both frequency and phase over a backplane. The method is applicable over any pair of shared transmission medium. The signal transmitted from the master to the slave is suitable for delivering a frequency reference and an approximate phase. The precise phase at the slave is obtained by delaying the 1PPS by a programmable amount estimated by measuring the round-trip delay between the master and slave.

Abstract: Systems and methods are disclosed for utilizing slave (receive) time-stamp clock rates that are different from master (sender) time-stamp clock rates to randomize and thereby reduce systematic time-stamp granularity errors in the communication of network packets. The slave (receive) time-stamp clock rate for some embodiments is set to be a fixed value that has a relationship with the master (sender) time-stamp clock rate such that the ratio of the slave (receive) clock rate to the master (sender) clock rate is a rational number. Other embodiments use a time-varying frequency for the slave (receive) time-stamp clock rate to randomize the slave (receive) time-stamp clock with respect to the master (sender) time-stamp clock. Additional time-stamps can also be generated using a slave (receive) time-stamp clock having a rate set to equal the rate of the master (sender) time-stamp clock signal.

Abstract: A method for implementing a distributed boundary clock in situations where book-end devices such as microwave TX/RX pairs must collaborate in achieving PTP on-path support is described. A dedicated channel, generally low-speed compared to the main channel is used to transfer timing from the master side to the slave side using framing and super-framing applied to the digital channel. Time-stamps of events such as super-frame boundaries are communicated between the two sides to enable timing transfer.

Abstract: Systems and methods are disclosed for utilizing slave (receive) time-stamp clock rates that are different from master (sender) time-stamp clock rates to randomize and thereby reduce systematic time-stamp granularity errors in the communication of network packets. The slave (receive) time-stamp clock rate for some embodiments is set to be a fixed value that has a relationship with the master (sender) time-stamp clock rate such that the ratio of the slave (receive) clock rate to the master (sender) clock rate is a rational number. Other embodiments use a time-varying frequency for the slave (receive) time-stamp clock rate to randomize the slave (receive) time-stamp clock with respect to the master (sender) time-stamp clock. Additional time-stamps can also be generated using a slave (receive) time-stamp clock having a rate set to equal the rate of the master (sender) time-stamp clock signal.

Abstract: Systems and methods are disclosed for direct passive monitoring of packet delay variation and time error in network packet communications. Packets traversing between slave and master clocks are monitored to provide direct results of the actual conditions without the need to rely upon inference determinations. Certain embodiments provide tap configurations to monitor packet flows, while certain other embodiments provide in-line configurations to monitor packet flows. Certain further embodiments provide multiple monitoring devices that can be used for passive monitoring purposes, such as passive monitoring to test boundary clock. These multiple monitoring devices can be configured to be within a single or different test instruments. Other variations are also described.

Abstract: Inclusion of a simple time-transfer module in client devices and judicious deployment of time-servers in the network enable a network management system to observe, record, and predict network issues. In a wireless network every mobile device can be a probe and monitoring of all parts of the network on a continuous basis can be achieved.

Abstract: Systems and methods are disclosed for direct passive monitoring of packet delay variation and time error in network packet communications. Packets traversing between slave and master clocks are monitored to provide direct results of the actual conditions without the need to rely upon inference determinations. Certain embodiments provide tap configurations to monitor packet flows, while certain other embodiments provide in-line configurations to monitor packet flows. Certain further embodiments provide multiple monitoring devices that can be used for passive monitoring purposes, such as passive monitoring to test boundary clock. These multiple monitoring devices can be configured to be within a single or different test instruments. Other variations are also described.

Abstract: A packet network that includes the distribution of timing information (time and frequency) between server and client devices can continue to operate in a holdover mode even when the server loses its primary timing reference based on GNSS. This is achieved by populating the packet network with some client devices that also have access to the same timing reference. These devices are used in a reverse timing transfer mode to provide a hack-up reference to the server and thereby provide a graceful solution to the problem of loss of reference.

Abstract: A master and slave module are described that facilitate the distribution of timing, both frequency and phase over a backplane. The method is applicable over any pair of shared transmission medium. The signal transmitted from the master to the slave is suitable for delivering a frequency reference and an approximate phase. The precise phase at the slave is obtained by delaying the 1PPS by a programmable amount estimated by measuring the round-trip delay between the master and slave.

Abstract: A Managed Timing Engine (MTE) provides a primary timing output synchronized to a selected input reference from a multiplicity of input references. Additional timing outputs can be generated such that there is a programmable frequency offset (in ppb) between them and the main output. The rate (in Hz) of the outputs can be programmable. The MTE can introduce a programmable delay for periodic phase references.

Abstract: Systems and methods are disclosed for direct passive monitoring of packet delay variation and time error in network packet communications. Packets traversing between slave and master clocks are monitored to provide direct results of the actual conditions without the need to rely upon inference determinations. Certain embodiments provide tap configurations to monitor packet flows, while certain other embodiments provide in-line configurations to monitor packet flows. Certain further embodiments provide multiple monitoring devices that can be used for passive monitoring purposes, such as passive monitoring to test boundary clock. These multiple monitoring devices can be configured to be within a single or different test instruments. Other variations are also described.

Abstract: Routes of a packet network are analyzed according to various transit delay metrics. Preferred packet network routes are selected between source and destination based on these metrics. In packet networks employing boundary clocks and transparent clocks, faulty boundary clocks and faulty transparent clocks are identified using the metrics.