Segment Routing Path Compression via Node SID Mapping

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In segment routing, excessively long identifier lists for data packets reduce transmission efficiency and degrade network performance, especially in large-scale networks with long SR tunnels.

Innovation Solution

A method to generate target information about the forwarding path by reducing the number of path identifiers, using node segment identifiers for unique shortest paths and adjacency segment identifiers for non-unique paths, thereby shortening the identifier list and improving transmission efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If detailed path information with multiple path identifiers is used to indicate the forwarding path, then the accuracy and completeness of path indication is improved, but the length of the identifier list increases excessively

Engineering Contradiction:
Improvepath indication accuracyVSAvoididentifier list length
Core Design Contradiction:
Measurement precisionVSLength of stationary object

Solution Approach 1:

The patent merges multiple path identifiers into a single node segment identifier that represents an entire sequence of nodes. Instead of listing each node identifier individually in the path, the invention combines them into a compressed representation that can be efficiently processed and stored, thereby reducing the identifier list length while maintaining path indication accuracy.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent extracts the essential forwarding information from detailed node-by-node path identifiers and retains only the critical node segment identifiers needed for path reconstruction. By removing redundant intermediate identifiers and keeping only the key routing information, the identifier list length is reduced while the essential path indication functionality is preserved.

Inventive Principle:
Principle #2Taking out (Extraction)

2Productivity

If the identifier list length is reduced by compressing path information, then data packet transmission efficiency is improved, but the complexity of path reconstruction increases

Engineering Contradiction:
Improvedata packet transmission efficiencyVSAvoidpath reconstruction complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent performs preliminary path computation and node segment identifier assignment before data packet transmission. The network controller pre-calculates the optimal path, assigns compressed node segment identifiers to represent sequences of nodes, and stores the mapping information in advance. This preliminary action eliminates the need for complex real-time path reconstruction at each network node, thereby improving transmission efficiency without significantly increasing operational complexity.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces a network controller as an intermediary that manages the compressed path representation. The controller maintains the mapping between compressed node segment identifiers and actual node sequences, performing path reconstruction centrally rather than at each network node. This intermediary approach simplifies the complexity at individual nodes while maintaining overall system efficiency.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP3806406B1Method and apparatus for obtaining information of forwarding path of data packet in segment routing
Publication Date: 2024.01.24 HUAWEI TECH CO LTD
  • EP3806406B1 patent drawingFigure 1~2
  • EP3806406B1 patent drawingFigure 3
  • EP3806406B1 patent drawingFigure 4

AI summary

This application provides a method and an apparatus for obtaining information about a forwarding path of a data packet in segment routing. In the method and the apparatus, when a first path indicated by a plurality of path identifiers in initial information is a unique shortest path from a start node on the first path to an end node on the first path, the first path may be indicated by using a node-SID of the end node on the first path instead of the plurality of path identifiers, so that a quantity of path identifiers can be reduced, data packet transmission efficiency can be further improved, and finally, performance of a communications network is improved.