A multi-node, quantum communication network for providing quantum-secure time transfer with Damon attack detection is described. The network includes three or more nodes connected via authenticated communication channels forming a closed loop. By determining differences between the local times at as well as the time durations required for photons to travel between the three or more nodes, the network detects a Damon attack, if present. For example, the network imposes a closed loop condition to detect the Damon attack. The network can also use the local time differences and time durations for photon travel between nodes to synchronize the local clocks at the three or more nodes of the network.

Embodiments of the present disclosure relate to methods, optical line terminals (OLTs), optical network units (ONUs), apparatuses and computer storage media for transmitting a time synchronization message. In some example embodiments, the OLT is configured to: determine a threshold rate to be N messages per second for transmission of a time synchronization message to an ONU, wherein N being greater than or equal to 0.1; and transmit, to the ONU, a time synchronization message at the threshold rate or a rate above the threshold rate, to enable the ONU to perform time synchronization with the OLT. In some other example embodiments, the OLT is configured to: select a plurality of ONUs for transmitting time synchronization information; and transmit, to the ONUs, a broadcast or multicast message the time synchronization information, to enable the plurality of ONUs to perform time synchronization with the OLT.

A sensor may determine a sampling pattern based on a group of synchronization signals received by the sensor. The sampling pattern may identify an expected time for receiving an upcoming synchronization signal. The sensor may trigger, based on the sampling pattern, a performance of a sensor operation associated with the upcoming synchronization signal. The performance of the sensor operation may be triggered before the upcoming synchronization signal is received.

Disclosed herein is a method, a computer program product, and a carrier for indicating one-way latency in a data network (N) between a first node (A) and a second node (B), wherein the data network (N) lacks continuous clock synchronization, comprising: a pre-synchronisation step, a measuring step, a post-synchronisation step, an interpolation step, and generating a latency profile. The present invention also relates to a computer program product incorporating the method, a carrier comprising the computer program product, and a method for indicating server functionality based on the first aspect.

Embodiments of a method and device are disclosed. In an embodiment, a method for synchronizing a slave clock in a Time Sensitive Network (TSN) that includes multiple Precision Time Protocol (PTP) clock domains is disclosed. The method involves determining parameters related to multiple PTP clock domains, assigning domain-specific weights to the multiple PTP clock domains based on the determined parameters, generating a control signal for a clock parameter using the domain-specific weights assigned to the multiple PTP clock domains, and adjusting the clock parameter of a slave clock in response to the control signal.

One embodiment of the present invention relates to a method for a reader to transmit and receive a signal to and from a tag, the method comprising: a step in which a first reader transmits a first signal to a tag; and a step in which the first reader receives the first signal reflected on the tag. The timing for the first reader to transmit the first signal is determined by using an offset value based on an ID related to the first reader.

A method of estimating a clock frequency offset in a mobile device relative to a clock frequency of a controller within a UWB network comprises (a) determining, for each of a plurality of anchors, an anchor clock frequency offset relative to the controller clock frequency, (b) broadcasting an anchor data packet from each anchor, the anchor data packet including the respective anchor clock frequency offset, (c) receiving at least one anchor data packet at the mobile device, (d) estimating a mobile device clock frequency offset relative to the anchor clock frequency of the anchor from which the at least one anchor data packet was received, and (e) estimating the clock frequency offset in the mobile device based on the estimated mobile device clock frequency offset and the anchor clock frequency offset included in the at least one received anchor data packet. Furthermore, a TDoA-based localization method and a TDoA-based localization system are described.

Disclosed herein is a method, a computer program product, and a carrier for indicating one-way latency in a data network (N) between a first node (A) and a second node (B), wherein the data network (N) lacks continuous clock synchronization, comprising: a pre-synchronization step. A measuring step, a post-synchronisation step, an interpolation step, and generating a latency profile. The present invention also relates to a computer program product incorporating the method, a carrier comprising the computer program product, and a method for indicating server functionality based on the first aspect.

A multi-channel and multi-zone audio environment is provided. Various inventions are disclosed that allow playback devices on one or more networks to provide an effective multi-channel and a multi-zone audio environment using timing information. According to one example, timing information is used to coordinate playback devices connected over a low-latency network to provide audio along with a video display. In another example, timing information is used to coordinate playback devices connected over a mesh network to provide audio in one or more zones or zone groups.

The communication master repeats transmission of first information indicating a counter value of a synchronization counter of the communication master to the one or more communication slaves through a network. Each of the one or more communication slaves updates the counter value of the synchronization counter of each of the one or more communication slaves based on the received first information upon receiving the first information from the communication master. The communication master manages a total number of pieces of the first information transmitted for each of the one or more communication slaves, and estimates synchronization accuracy with respect to the communication master for each communication slave based on a number of transmissions of the first information for each communication slave.