A method for functionally secure connection identification for data exchange via a telegram between a source data service and a sink data service, wherein whether the time stamp of an incoming telegram is older than the time stamp of a predecessor telegram is determined, upon receipt of the predecessor telegram a monitoring counter being started and whether the currently incoming telegram has arrived within a monitoring time is additionally determined, where a local time stamp of a local time basis is compared with the associated time stamp of the incoming telegram and whether a comparison difference does not exceed a period of time is determined, a telegram arriving only being accepted as valid if the time stamp of the arriving telegram is greater than the time stamp of the telegram most recently accepted as valid, and data is valid if the checks are positive, otherwise a fail-safe reaction is triggered.

Methods and apparatus for data plane control of network time sync protocol in multi-host systems. A network interface controller (NIC) is configured to implement a network data plane that is associated with a software-based control plane implemented in the multi-host system. The NIC includes a primary timer and secondary timers at distributed endpoints such as network ports. The NIC receives network time packets having network timestamps and employs a secondary timer to associate a local timestamp with the packets. The network and local timestamps are compared by a network intellectual property block (network IP) in the data plane datapath to adjust the primary and secondary timer(s) to match the network time. The network IP uses a 2-bit wire protocol to increment and/or decrement the primary and secondary timer(s) that enables the timers to be adjusted with a nanosecond granularity.

A network device receives a packet that conforms to a protocol that i) defines a time stamp field, ii) does not define a dedicated field for time correction information, and iii) defines a plurality of general purpose extension fields. The packet includes (i) a time stamp generated by a source node in the time stamp field, and (ii) a time correction value corresponding to multiple ones of the plurality of intermediate nodes, the time correction value being located in one of the general purpose extension fields. The network device identifies (i) a time specified by the time stamp, and (ii) time correction information specified in the one general purpose extension field, and uses the time correction information and the time specified by the time stamp to synchronize a clock maintained by the network device to a clock maintained by the source node.

A shared bus time interleaves 1 PPS signal and control and coordination information between a primary timing source and line cards that need to be synchronized using the 1 PPS signals. The shared bus utilizes 1 second frames divided into time slots. The 1 PPS signals are interleaved at predetermined locations in the frame so the delays introduced by interleaving the 1 PPS data in time can be precisely removed. While the bus is not being used for 1 PPS signals, the bus is available to send control and coordination information between the line cards and the primary timing source, avoiding the use of another system and increasing utilization of an available communication path.

Embodiments disclosed herein provide techniques to selectively distribute Precision Time Protocol (PTP) data in a network. The network can include multiple different network devices (e.g., switches) connected to form a network architecture (e.g., a spine/leaf architecture). Rather than distributing the PTP data (e.g., PTP timestamps) through all the network devices in order to synchronize local clocks to a global, master clock, the embodiments herein describe an out-of-band distribution network which selectively distributes the PTP data to select network devices in the network.

In order to simplify calculation of delay time lengths in a time synchronization device in a packet network, when executing time synchronization using a synchronization signal sent via the packet network, this time synchronization device 20 includes: a data receiving unit 21 that receives synchronization information including a time correction field used when correcting synchronization time information in a client device 30; a before-data-processing time correcting unit 22 that updates the time correction field by subtracting information indicating a time at which synchronization information is received, from the time correction field; an after-data-processing time correcting unit 23 that updates the time correction field by adding information indicating a time after performing data processing on the synchronization information, to the time correction information of the time correction field updated by the before-data-processing time correcting unit 22; and a data sending unit 24 that sends the updated synchronization information to the client device 30.

[Problem] It is possible to improve the quality of time information by suppressing a jump in time which arises when switching a transfer path in a BC apparatus to which transfer paths of time information of at least 2 systems are connected to an input side.

[Solution] A time synchronization apparatus 20 is mounted on a BC apparatus 12c in which two systems of at least a 0-system route (0-system) and a 1-system route (1-system) are connected to an input side, and includes a time correction value holding unit 26 configured to hold a 0-system correction value in which a time error resulting from delay of UTC due to performance inherent to the BC apparatus is the same value as a time error accumulated on the 0-system side and a 1-system correction value in which the time error is the same value as a time error accumulated on the 1-system side. Further, a failure restoration detection unit 23 configured to detect a failure in the 0-system or the 1-system, a time calculation unit 24 configured to perform correction by subtracting a 1-system correction value relating to a normal 1-system from UTC having time error accumulated on the normal 1-system side, when a failure in the 0-system is detected, and a path switching unit 25 configured to switch to the normal 1-system side such that the UTC after correction is transferred, when the failure is detected, are included.

A chromatograph and a method of acquiring and displaying a real-time chromatogram using time-stamped asynchronous messaging are provided. The method includes generating a chromatogram of a sample, acquiring segments of data points of the chromatogram in real-time, annotating in real-time the segments of data points of the chromatogram with timing stamps of cycle events of an analysis cycle using time-stamped event messages, receiving the time-stamped event messages asynchronously and displaying each cycle event of the cycle events of the analysis cycle and each segment of the segments of data points of the chromatogram in a display module as being received.

A PHY constituted of: a clock arranged to generate a time signal indicative of the current time; and an egress stamp functionality arranged to: receive a data packet on the egress side, extract data from a predetermined section of the received data packet, and responsive to the extracted data, perform one of a plurality of predetermined timestamp operations, the plurality of predetermined timestamp operations comprising: generating a timestamp signal responsive to the generated time signal; not generating a timestamp signal; or modifying a timestamp written in the received data packet.

A network device may assign, to a port of a plurality of ports on the network device, a precision timing protocol (PTP) port priority for PTP communications between the network device and another network device. The network device and the other network device may be communicatively connected via a plurality of links in a link aggregation group (LAG). Each port, of the plurality of ports, may be associated with a respective link, of the plurality of links, in the LAG. The network device may generate a link layer discovery protocol (LLDP) frame that includes information identifying the PTP port priority assigned to the port. The network device may transmit the LLDP frame to the other network device to identify, to the other network device, the PTP port priority.