PTP Multi-Time Domain Synchronization Using Offset Clock Layers

Solution Overview

Problem

Existing Precision Time Protocol (PTP) standards, such as 802.1AS-2011 (gPTP), lack specifications for synchronizing multiple time domains, leading to increased costs and resource consumption when physically reconfiguring networks for time synchronization across different time zones.

Innovation Solution

A method and apparatus for PTP-based time synchronization across multiple time domains, involving a master node and a slave node, using PTP and offset clock layers to transmit reference times and offsets, allowing synchronization across various time domains without requiring additional hardware.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If physically reconfiguring the network by adding separate hardware devices is used for time synchronization across multiple time domains, then time synchronization capability is improved, but device complexity and resource consumption increase

Engineering Contradiction:

Improvetime synchronization capabilityVSAvoidnetwork reconfiguration complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies multi-functionality by enabling a single PTP hardware device to perform time synchronization across multiple time domains simultaneously. The system uses time domain offset information to allow one device to serve multiple time zones without requiring separate hardware for each time domain, thereby reducing device complexity while maintaining synchronization capability.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent changes the parameter approach by introducing time domain offset values that can be configured in software. Instead of physically reconfiguring the network topology for each time domain, the system adjusts time synchronization by modifying offset parameters, allowing flexible adaptation to multiple time domains without hardware changes.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If physically reconfiguring the network by adding separate hardware devices is used for time synchronization across multiple time domains, then time synchronization capability is improved, but resource consumption increases

Engineering Contradiction:

Improvetime synchronization capabilityVSAvoidhardware resources

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The patent applies multi-functionality by enabling a single PTP hardware device to perform time synchronization across multiple time domains simultaneously. The system uses time domain offset information to allow one device to serve multiple time zones without requiring separate hardware for each time domain, thereby reducing device complexity while maintaining synchronization capability.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent uses virtual copying by creating virtual time domain instances through software configuration. Instead of deploying physical duplicate hardware devices for each time domain, the system copies time synchronization functionality through virtual offset configurations, reducing the quantity of physical hardware resources needed.

Inventive Principle:

Principle #26Copying

3Ease of operation

If conventional PTP is used for single time domain synchronization, then implementation simplicity is maintained, but adaptability to multiple time domains is reduced

Engineering Contradiction:

ImprovePTP implementation simplicityVSAvoidmulti-time domain support

Core Design Contradiction:

Ease of operationVSAdaptability or versatility

Solution Approach 1:

The patent applies segmentation by dividing the time synchronization function into separate time domain components. Each time domain is handled as an independent unit with its own offset configuration, allowing the system to maintain simple PTP operations within each domain while extending versatility across multiple domains through modular offset management.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces time domain offset information as an intermediary element between the PTP protocol and multiple time domains. This offset mechanism acts as a mediator that translates single-time-domain PTP operations into multi-time-domain synchronization, maintaining implementation simplicity while enabling adaptability to different time zones.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS12483345B2Method for synchronizing time in multiple time domains, and apparatus implementing the same method

Publication Date: 2025.11.25 HYUNDAI AUTOEVER

AI summary

A method of synchronizing time across a plurality of time domains between a master node and a slave node is provided. The method comprises transmitting, by the master node, a reference time indicated by a hardware clock of the master node to the slave node, synchronizing, by the slave node, a hardware clock of the slave node to the reference time indicated by the hardware clock of the master node, transmitting, by an offset clock layer of the master node, an offset of a first time domain among the plurality of time domains to an offset clock layer of the slave node, and obtaining, by the PTP layer of the slave node, a time in the first time domain by applying the offset of the first time domain to a reference time indicated by the hardware clock of the slave node.