Abstract: A method for measuring one-way delays in a communications network, the method comprising: maintaining, at a third node having a reference clock, a first virtual clock state emulating a first node clock located at a first node and a second virtual clock state emulating a second node clock located at a second node; registering a timeset comprising transmission and reception times at the first node and the second node, respectively, for each packet of a plurality of packets that are transmitted from the first node to the second node and reflected from the second node back to the first node; converting times in the timeset, responsive to the first and/or second virtual clocks, into times in accordance with the reference clock; calculating, for each packet of the plurality of packets, a forward one-way delay (FOWD) and a reverse one-way delay (ROWD), responsive to the converted timeset.

Abstract: A method for measuring one-way delays in a communications network, the method comprising: maintaining, at a third node having a reference clock, a first virtual clock state emulating a first node clock located at a first node and a second virtual clock state emulating a second node clock located at a second node; registering a timeset comprising transmission and reception times at the first node and the second node, respectively, for each packet of a plurality of packets that are transmitted from the first node to the second node and reflected from the second node back to the first node; converting times in the timeset, responsive to the first and/or second virtual clocks, into times in accordance with the reference clock; calculating, for each packet of the plurality of packets, a forward one-way delay (FOWD) and a reverse one-way delay (ROWD), responsive to the converted timeset.

Abstract: A method for measuring one-way delays in a communications network, the method comprising: maintaining a virtual clock state comprising information for converting times measured with respect to remote clocks into times as would be measured with respect to a local reference clock; registering, for each packet of the plurality of packets in a communications session between the first and second nodes, a timeset comprising transmission and reception times at the first and second nodes; converting, responsive to the virtual clock, times in the timeset measured with respect to the first node clock or the second node clock, into times as would be measured with respect to the reference clock; calculating, for each packet of the series of packets, a forward one-way delay (FOWD) from the first node to the second node and a reverse one-way delay (ROWD) from the second node to the first node, responsive to the converted timeset.

Abstract: Apparatus for synchronizing a local clock to a master clock, the apparatus comprising: at least one port for receiving and transmitting packets; a local clock; and a packet inspector that uses time from the local clock to timestamp packets received at a port of the at least one port, copies timing information from the received packets if the packets are timing distribution packets that are transmitted between a master clock and a slave clock in order to synchronize the slave clock to the master clock, and forwards the received packets for transmission from a port of the at least one port towards a packet destination that is not a packet source from where the packets originate, wherein the local clock uses the copied timing information and timestamps to synchronize the local clock to the master clock.

Abstract: Apparatus for synchronizing a local clock to a master clock, the apparatus comprising: at least one port for receiving and transmitting packets; a local clock; and a packet inspector that uses time from the local clock to timestamp packets received at a port of the at least one port, copies timing information from the received packets if the packets are timing distribution packets that are transmitted between a master clock and a slave clock in order to synchronize the slave clock to the master clock, and forwards the received packets for transmission from a port of the at least one port towards a packet destination that is not a packet source from where the packets originate, wherein the local clock uses the copied timing information and timestamps to synchronize the local clock to the master clock.

Abstract: Apparatus for monitoring a packet switched network, the apparatus comprising: at least one port for receiving and transmitting packets; a local clock; and a packet inspector that uses time from the local clock to timestamp packets received at a port of the at least one port, and additionally copies timing information from received timing distribution packets, which are transmitted from a master clock to a slave clock in order to discipline the slave clock, and forwards the received packets for transmission from a port of the at least one port; wherein the apparatus uses the timestamp of a received timing distribution packet and the copied timing information to monitor timing distribution performance of the network.

Abstract: Apparatus for monitoring a packet switched network, the apparatus comprising: at least one port for receiving and transmitting packets; a local clock; and a packet inspector that uses time from the local clock to timestamp packets received at a port of the at least one port, and additionally copies timing information from received timing distribution packets, which are transmitted from a master clock to a slave clock in order to discipline the slave clock, and forwards the received packets for transmission from a port of the at least one port; wherein the apparatus uses the timestamp of a received timing distribution packet and the copied timing information to monitor timing distribution performance of the network .