TSN Sequence Recovery with Extended Future Acceptance Range

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing IEEE 802.1CB standard for sequence recovery in time-sensitive networks (TSN) is overly restrictive, leading to unnecessary packet discards when sequence generation and recovery functions are based on the source address, particularly in unicast scenarios, due to a limited acceptance range that does not account for out-of-order packet arrival.

Innovation Solution

A sequence recovery method that expands the acceptance range by defining a future range with a length greater than the history range, allowing for a more flexible and hardware-efficient handling of sequence numbers, thereby reducing incorrect packet discards.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the sequence recovery function uses a limited acceptance range based on the IEEE 802.1CB standard, then the sequence recovery process is simple and hardware-efficient, but packets may be incorrectly discarded when they arrive out of order

Engineering Contradiction:
Improvepacket acceptance accuracyVSAvoidsequence recovery function complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies dynamics by making the future range configurable and adjustable rather than fixed. The system allows dynamic modification of the future range length to adapt to different network conditions and requirements, enabling the sequence recovery function to balance between reliability and complexity based on actual operational needs

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameter of acceptance range by introducing an asymmetric design where the future range length can be independently configured to be greater than the history range length. This parameter change allows the system to accept packets that are ahead of the current sequence without requiring complex state tracking, thereby improving reliability while maintaining hardware efficiency

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the future range length is increased to accommodate out-of-order packets, then packet acceptance accuracy improves, but the sequence recovery function becomes more complex

Engineering Contradiction:
Improvereduction of incorrect packet discardsVSAvoidacceptance range management complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies asymmetry by designing the future range to be longer than the history range. This asymmetric configuration reflects the actual network behavior where packets are more likely to arrive ahead of sequence than behind sequence, allowing the system to optimize for the more common scenario while keeping the complexity manageable

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The patent applies local quality by treating the future range and history range differently with different length configurations. The future range is optimized for accommodating out-of-order packets with a longer length, while the history range maintains a shorter length for efficient duplicate detection, creating locally optimized quality in each range

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP4099647B1Extending acceptable sequence range
Publication Date: 2026.04.15 NXP BV
  • EP4099647B1 patent drawingFigure 1~2
  • EP4099647B1 patent drawingFigure 3~4
  • EP4099647B1 patent drawingFigure 5~6

AI summary

A sequence recovery method executed by a node in a time-sensitive network, the method comprising receiving a packet having a sequence number, determining whether the sequence number is within a predetermined range of a reference sequence number, wherein the reference sequence number is a current latest sequence number accepted by the node, and wherein the predetermined range comprises a history range and a future range, wherein the history range has a length equal to a history length and includes the reference sequence number and a predetermined number of consecutive sequence numbers that are immediately earlier than the reference sequence number, and the future range has a length equal to a future length and defines a predetermined number of consecutive sequence numbers that are immediately later than the reference sequence number, wherein the future length is greater than the history length.