This disclosure provides a method for sending and receiving a clock synchronization packet in FlexE. The method includes: generating, by a sending apparatus, indication information and a plurality of data blocks, where the plurality of data blocks are obtained by encoding a first clock synchronization packet, the indication information is used to indicate a first data block, and the first data block is a data block used for timestamp sampling in the plurality of data blocks; determining, by the sending apparatus, according to the indication information, a moment at which the first data block arrives at a medium dependent interface MDI of the sending apparatus, and generating a sending timestamp, where the sending timestamp is used to record a sending moment of the first clock synchronization packet; generating a second clock synchronization packet carrying the sending timestamp; and sending, by the sending apparatus, the second clock synchronization packet.

The present disclosure is related to transmitting and receiving media channels, such as audio and video channels. These channels may be transmitted as packets from one or more transmitting devices to one or more receiving devices for playout. Certain embodiments of the present disclosure include systems, methods, and computer-readable media for determining latency of a data network for synchronised playout of received signals. Additionally, certain embodiments of the present disclosure include systems, methods, and computer-readable media for synchronising playout among devices connected to a data network.

This disclosure provides a method for sending and receiving a clock synchronization packet in FlexE. The method includes: generating, by a sending apparatus, indication information and a plurality of data blocks, where the plurality of data blocks are obtained by encoding a first clock synchronization packet, the indication information is used to indicate a first data block, and the first data block is a data block used for timestamp sampling in the plurality of data blocks; determining, by the sending apparatus, according to the indication information, a moment at which the first data block arrives at a medium dependent interface MDI of the sending apparatus, and generating a sending timestamp, where the sending timestamp is used to record a sending moment of the first clock synchronization packet; generating a second clock synchronization packet carrying the sending timestamp; and sending, by the sending apparatus, the second clock synchronization packet.

A radio receiver apparatus comprises radio circuitry for receiving a sequence of radio data packets, transmitted at regular intervals, wherein the sequence of radio data packets encodes a digital audio stream and each radio data packet encodes a respective number of audio samples from the digital audio stream. The apparatus also comprises a digital audio interface for outputting audio samples from the received digital audio stream, a controllable oscillator arranged to control an output rate at which the audio samples are output from the digital audio interface, and a timer. The apparatus also comprises control logic, configured to use the timer to measure an interval between receiving each of a pair of the radio data packets, and to control the oscillator to vary the output rate incrementally, in a number of steps, while outputting the audio samples from one radio data packet. The number of steps, or the size of each step, or both, depends on the measured interval.

A networked system is provided for transporting digital media packets, such as audio and video. The network includes network devices interconnected to send and receive packets. Each network device can receive and transmit media signals from media devices. A master clock generates a system time signal that the network devices use, together with a network time protocol to generate a local clock signal synchronised to the system time signal for both rate and offset. The local clock signal governs both the rate and offset of the received or transmitted media signals. The system, which can be implemented using conventional network equipment enables media signals to be transported to meet quality and timing requirements for high quality audio and video reproduction.

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.

An audio playback system that includes audio playback devices each including a communication module, a playback module and a processing module is provided. The communication module receives a beacon signal and audio signal packets and generates an interrupt signal. The processing module receives the interrupt signal to retrieve an audio source timestamp corresponding to an audio source system time from the beacon signal, compares the audio source timestamp with an internal time generated based on an internal system time when the beacon signal is received to calculate a difference therebetween, receives a playback initialization signal from the audio source device that includes an audio source system playback initialization time, calculates an internal system playback initialization time according to the difference and the audio source system playback initialization time and controls the playback module to playback the audio signal packets from the internal system playback initialization time.

An audio system, method, and computer program product for synchronizing device clocks. The systems, methods and computer program product can establish a first isochronous data stream between a peripheral device and a first device and establish a second isochronous data stream between the first device and a second device to send data between the first and second device. As the two data streams may rely on two different device clocks, e.g., one clock which defines the timing for the first isochronous data stream and a second clock which defines the timing for the second isochronous data stream, the systems, methods, and computer program disclosed herein are configured to maintain synchronization and/or synchronize the first clock with the second clock to prevent data loss due to clock drift.

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.

A networked system is provided for transporting digital media packets, such as audio and video. The network includes network devices interconnected to send and receive packets. Each network device can receive and transmit media signals from media devices. A master clock generates a system time signal that the network devices use, together with a network time protocol to generate a local clock signal synchronised to the system time signal for both rate and offset. The local clock signal governs both the rate and offset of the received or transmitted media signals. The system, which can be implemented using conventional network equipment enables media signals to be transported to meet quality and timing requirements for high quality audio and video reproduction.