The embodiments of the present invention provide a method for heartbeat packet processing by using a proxy, an apparatus, and a communications system. The method includes: receiving, by a host, a first heartbeat packet sent by a first application in a client, where the client is a terminal that accesses the host by using a short range communications technology; and determining, by the host according to the first heartbeat packet and a first preset list, whether the first application is included in the first preset list. Thus, an objective of saving power for the host and the client can be achieved.

This invention relates to methods and systems for estimating offset and skew using linear programming. Embodiments of the invention relate to methods and systems which apply linear programming principles to links with asymmetric transmission rates which are estimated from an exchange of timing messages (for example under IEEE 1588 PTP). Further embodiments provide for the estimation of clock offsets using linear programming techniques when the skew is known or estimated.

Disclosed are techniques for timing correction for a DOCSIS Edge-QAM. Unlike the DTI required at the headend in existing solutions for DOCSIS Edge-QAM timing, the disclosed techniques may use an Edge-QAM timing deeper in to the network. The N-QAM, referring to an Edge-QAM that is deeper in the network, may be in the optical node configured to convert signals from a network headend or hub for delivery to a subscriber network element. The N-QAM device located in the node may include a local clock for deriving a local time for incoming transport streams, modulating the transport streams onto a downstream carrier for delivery to subscriber network elements using the local clock time, and adjusting the local clock time based on an average value of timestamps in the incoming transport streams.

Systems, methods, and computer-readable media for annotating process and user information for network flows. In some embodiments, a capturing agent, executing on a first device in a network, can monitor a network flow associated with the first device. The first device can be, for example, a virtual machine, a hypervisor, a server, or a network device. Next, the capturing agent can generate a control flow based on the network flow. The control flow may include metadata that describes the network flow. The capturing agent can then determine which process executing on the first device is associated with the network flow and label the control flow with this information. Finally, the capturing agent can transmit the labeled control flow to a second device, such as a collector, in the network.

A differential protection device monitors a first object to be protected in an electrical energy supply network. The differential protection device has a measuring unit configured to acquire measurement values at one end of the first object to be protected, a communication unit configured to exchange measurement values with a differential protection device arranged at another end of the first object to be protected, the communication unit has a physical interface for transmitting and receiving the measurement values, and an evaluation unit configured to form a differential value and to generate a fault signal indicating a fault with regard to the first object to be protected if the differential value exceeds a predefined threshold value. Ideally, the differential protection device is configured to monitor further objects to be protected and to exchange respective further measurement values with regard to each further object to be protected.

A mapper physical layer device (PHY) is disclosed that performs a protocol conversion of an input data stream that is formatted according to a first wired communication protocol to provide an output data stream that is formatted according to a second wired communication protocol. The mapper PHY can be synchronized to a common reference clock or clocking source to ensure that data streams provided by multiple mapper PHYs are sufficiently aligned to satisfy frame timing alignment accuracy requirements of a wireless communication protocol.

A method and system for the post-adjustment (i.e., offline) of event timestamps to implement virtual time synchronization amongst detection node clocks. In existing methodologies with the goal of clock synchronization, clocks (and timestamps generated therefrom) are disciplined or adjusted at the recordation time of the events on a detection node (e.g., a switch/router, an Internet-of-Things (IoT) device, a wireless sensor, etc.). However, there is no particular reason for these clocks or timestamps to be accurate during the recordation time, but rather, should be accurate at their use or interpretation time. Further, through these recordation time adjustments, clock drifts and timing errors may be gradually introduced, leading to runaway inaccuracies. The disclosed method and system intentionally avoids the disciplining of clocks at event recordation times on the detection node and, instead, adjusts timestamps during interpretation times, to overcome the aforementioned issues.

In one embodiment, a local clock is synchronized to a master clock using a Kalman filter to determine state variables using a state transition matrix that includes at least one coefficient that is associated with a digital-to-analog converter (DAC), where the state variables include a unit step variable indicative of a unit step for the system. The local clock is controlled based on the state variables determined using the Kalman filter. The unit step is indicative of an amount by which the frequency of the local clock signal changes in response to a change in the digital input of the DAC.

An aspect of the present disclosure enables each receiver node of a wireless network to synchronize active widows with those of the sender node. In an embodiment, a receiver node receives a packet from a sender node on a wireless network, with the packet including data indicating a position of the packet in an active window of the sender node. The receiver node determines the position at which the packet is received in an active window of the receiver node. The receiver node determines a difference between the two positions and adjusts a start position of the next active window (of the receiver node) based on the determined difference to synchronize the future active windows at the receiver node to respective active windows at the sender node.

A heartbeat packet timer identification method and a device, where the identification method is performed by a device that sets a timer, and the method includes determining, in a data packet transmitted by the device, each associated data packet corresponding to each timing end moment of the timer and determining, according to each associated data packet and each timing end moment of the timer, whether the timer is a heartbeat packet timer set by the device for transmitting a heartbeat packet. With reference to a data packet transmitted by a device and each associated data packet that corresponds to each timing end moment of a timer, the heartbeat packet timer identification method and the device may determine with relatively high accuracy whether the timer is a heartbeat packet timer.