Systems and methods for supporting multiple time synchronization protocols within an industrial device include obtaining a time reference from each industrial device within the first set of industrial devices and the second set of industrial devices. The time reference provides the basis for synchronization of the clock and other clocks of first set of industrial devices and the second set of industrial devices. A principal time reference is selected from among the time references. Once selected, the principal time reference is correlated with each of the time references obtained from the first set of industrial devices and the second set of industrial devices. With the principal time reference correlated, related communication with the second device may be controlled.

[Problem to be Solved] Optimizing a route of time synchronization in a network including apparatuses with different types of precision classes. [Solution to the Problem] A time transmission system includes BC nodes 200 with different types of apparatus performances, and multiple routes of PTP packets from GM nodes 101 and 102 to a BC node 220 via the BC node 200 are present. Each BC node 200 located upstream on a route performs notification of performance information indicating its apparatus performance to the BC node 200 located downstream with respect thereto. The BC node 220 includes a determination index calculation unit 11 that calculates a determination index for each route by referencing the performance information notified from the BC nodes 200 located upstream on each route, and a route selection unit 12 that selects a route for transmitting and receiving PTP packets from multiple routes of PTP packets to the BC node 220, based on the calculated determination index for each route.

The present application generally relates to network timing synchronization in the presence of link faults including apparatus and methods In various embodiments, a method includes generating a time synchronization signal, transmitting the time synchronization signal from a first switch to a second switch via a first link and from the first switch to a third switch via a second link, detecting a link failure of the first link, and transmitting the time synchronization signal from the second switch to the third switch via a third link in response to the link failure.

A method for synchronizing a logical clock in a device comprising a physical clock, an input port, and an output port, the device further comprising a logical clock and a time compensation clock sharing the physical clock, the time compensation clock making it possible to determine a residence time, comprising obtaining a theoretical residence time, during a pre-synchronization phase according to which the logical clock is not synchronized, adding a value representative of the obtained theoretical residence time to a residence time value stored in a synchronization message to be forwarded, during a synchronization phase according to which the logical clock is synchronized, obtaining a residence time and adding a value representative of the obtained residence time to a residence time value stored in a synchronization message to be forwarded, and synchronizing the logical clock as a function of a residence time value stored in a received synchronization message.

A node may determine the topology of a computation system. The computation system is a network of nodes and multiple nodes are capable of being a grandmaster clock source. The method includes starting a best clock selection process, announcing clock information, and if the node is not acting grand master then receiving messages announcing clock information from other nodes of the network. Topology information is extracted from the messages, and if the node is acting grandmaster then retiring from the position of grandmaster. The best clock selection process steps are repeated until no node of the network becomes acting grandmaster.

A method performed by a transmitting device, in a 3GPP wireless communication 5 system (100), for handling generalized Precise Timing Protocol (gPTP) signaling, from a Time Sensitive Network (TSN) is provided. The transmitting device receives (1301) a gPTP frame from the TSN network. The gPTP frame comprises time information, an indication of a time domain related to the time information and/or a Medium Access Control (MAC) address of a second end station connected to a receiving device. Based 10 on the indication of the time domain and/or the MAC address, the transmitting device determines (1302) the receiving device which the gPTP frame relates to. The transmitting device transmits (1304), to the determined receiving device, the gPTP frame in a PDU session related to the determined receiving device.

Methods, systems, and devices for wireless communications are described. A first node (e.g., a user equipment (UE)) may receive a timing synchronization signal from a second node (e.g., a base station) over a cellular wireless communication link. In some aspects, the timing synchronization signal may indicate mapping information to synchronize the first node with the second node. The mapping information may be for synchronizing a first time of a first clock of the first node to a second time of a second clock of a second node. The first node may synchronize the first time of the first clock to the second time of the second clock based at least in part on the mapping information and the synchronization information. The first node may transmit a timing control based on a timing of the second clock to a device connected to the first node via a local wired interface.

A control method and a time aware bridge device for a seamless Precision Time Protocol (PTP) are provided. The control method includes: utilizing the time aware bridge device to pre-configure a first control signal source as a master control signal source, and pre-configure a second control signal source as a backup control signal source; utilizing the time aware bridge device to determine whether one or more packets from the master control signal source conform to at least one predetermined rule to generate a determination result; and selectively configuring the second control signal source as the master control signal source according to the determination result.

The Digital Time Processing over Time Sensitive Networks (DTP TSN) disclosed herein is contributing methods, systems and circuits for using a Precision Time Protocol (PTP) such as IEEE 1588 for distributing a master time secured by a master unit to slave units by utilizing slave clocks recovered from PTP messages and/or compatible with them data receiver clocks for maintaining a local slave time which is increased to a local master time by adding to it an estimate of a transmission delay derived by processing PTP messages, wherein such distribution of the master time includes filtering out phase noise of a timing referencing signals communicated by PTP messages in order to produce accurate timing implementing signals such as the slave clock, local slave time and local master time.

A first network device may receive, from a second network device, a clock quality indication that is associated with a clock of the second network device, wherein the clock of the second network device is a reference clock for a network that includes the first network device and the second network device. The first network device may determine, based on a clock signal of the second network device, that a quality metric of the clock does not satisfy a threshold. The first network device may provide, to the second network device, a clock fault notification to cause the second network device to downgrade the clock quality indication transmitted by the second network device. The first network device may select a new reference clock for the first network device based on receiving the downgraded clock quality indication from the second network device.