Precision Time Protocol

About: Precision Time Protocol is a research topic. Over the lifetime, 604 publications have been published within this topic receiving 6006 citations. The topic is also known as: PTP & IEEE 1588.

Research for Increasing Accuracy of IEEE1588 Protocol in the VLAN

Abstract: IEEE1588 precision time protocol (PTP) is a time synchronization protocol that is specially designed for measurement and control field. It is widely used in many fields for high clock synchronization precision, strong stability, low cost etc. In this paper, we study how to make full use of VLAN tag field to improve PTP packets forwarding priority in the second layer switch supporting VLAN, so can reduce jitter and error caused by PTP packets in the network transmission and implement nanosecond precision.

Avoiding contention between synchronization packets and in-phase and quadrature (iq) packets communicated over fronthaul of a radio access network

Abstract: Techniques are described for avoiding contention between synchronization packets (for example, Institute of Electrical and Electronics Engineers (IEEE) 1588 Precision Time Protocol (PTP) synchronization packets) and in-phase and quadrature (IQ) packets communicated over a fronthaul network used in a radio access network (for example, a Fifth Generation (5G) radio access network).

System and Method for Synchronization of Signal

Abstract: Provided are a system and a method for synchronizing a signal, capable of efficiently operating a system and a network by a management system managing a clock synchronization schedule, and by increasing reliability of communication through synchronization of a clock signal between base stations. The system for synchronizing the signal includes: an institute of electrical and electronics engineers (IEEE) 1588 master including a precision time protocol (PTP) generator for generating a reference clock based on an IEEE 1588 standard; a plurality of devices for correcting a system clock of an oscillator based on the reference clock generated from the PTP generator; and a management system for managing a clock synchronization schedule of the devices.

Precision time protocol grandmaster clock : Systemization and development of the protocol handler and functional blocks on FPGA

Abstract: Considering the growth in demand of for instance real-time video services, it is apparent that higher constraints are placed upon timing and synchronization and is hence mission critical for the next generation network infrastructures. One major way in which carriers have been coping with this, is by employing a packet-based timing distribution such as IEEE 1588 Precision Time Protocol (PTP). With the second version of the Protocol even used in the Large Hadron Collider at CERN, amongst various other application areas (such as the telecom industry), it is a testament to that PTP is a viable time and frequency synchronization solution with enough interest from a wide range of application groups. Synchronization protocols require a highly accurate and stable timing source, which serves as the synchronization topology’s primary reference (known as the Grandmaster Clock within PTP). Besides providing navigation assistance, GPS also provides such accurate time reference dissemination at the cost of a GPS-receiver. Thus GPS is a popular choice for a time reference source in synchronization protocols such as PTP.The main result of this thesis, a PTP Grandmaster Clock, has been developed and functionally verified on an FPGA. A GPS-receiver serves as the time reference source in the system where periodic time and date information is updated and then inserted into PTP messages, which in turn are distributed over Ethernet to PTP Slave Clocks. In the absence of a PTP Slave clock, a laptop emulated the behavior of a PTP Slave Clock in order functionally verify the Grandmaster Clock implementation. This was done using Wireshark and Ostinato that together serve as a network packet analyzer to verify the packets transmitted from the Grandmaster and a packet-generation software to mimic a PTP Slave Clock respectively.Although outside the scope of the thesis, a simpler characterization using a synchronization protocol evaluation tool (the IXIA Anue 3500) has been performed in order to evaluate the initial performance of this implementation.Despite the performance not being on par with similar final implementations of PTP Grandmaster Clock, some key areas that require further effort have been identified. These areas include to some extent a redesign but mostly on replacing system infrastructure blocks with more deterministic and IEEE 1588-compliant IP blocks, i.e. the Ethernet MAC IP block.It is believed that once these recommended changes are followed, the implementation would be capable of achieving the potential synchronization accuracy necessary for modern application needs.

Time synchronization method between CAN-FD nodes

Abstract: Recently, advanced driver assistance systems (ADAS) have gained prominence in the vehicle industry, with respect to the importance of the stability and reliability of vehicular control technology or communication technology. In such situations, when data is transmitted, communication delays between different networks occur inevitably, and if the electronic control units (ECU) of each sensor are not time-synchronized, they result in control process issues of the ADAS. In this paper, we propose a time synchronization method of each node of the CAN-FD network by applying the end-to-end (E2E) mechanism of applying the precision time protocol (PTP).