BIER Forwarding with User Side Node Identification

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In IPv6 networks using BIER technology, packets cannot be correctly received by user side nodes due to failure in identifying the user side node, as existing multicast and routing protocols like MLD/IGMP, PIM, Babel, OSPF, ISIS, and BGP cannot distinguish between host and router or switch reports, leading to incorrect forwarding.

Innovation Solution

Introducing a user side flag in multicast and routing protocol messages, such as MLD, IGMP, PIM, Babel, BGP, OSPF, and ISIS, to differentiate user side node requests and advertisements, ensuring correct packet forwarding by encapsulating destination addresses specific to user side nodes within the BIER forwarding table.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If existing multicast and routing protocols (MLD/IGMP, PIM, Babel, OSPF, ISIS, BGP) are used for packet forwarding, then network routing and multicast functionality is provided, but user side nodes cannot be correctly identified leading to packet misdirection

Engineering Contradiction:
Improvepacket forwarding accuracyVSAvoiduser side node identification information
Core Design Contradiction:
ReliabilityVSLoss of information

Solution Approach 1:

The patent modifies the routing protocol message structure by adding a new parameter (flag bit) to distinguish user side nodes from router nodes. This parameter change enables the existing protocols to carry additional identification information without requiring complete protocol redesign, thereby improving packet forwarding accuracy while maintaining backward compatibility.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces an intermediary mechanism (flag bit in routing messages) that mediates between the routing protocol and the BIER forwarding table. This intermediary carries identification information that enables correct routing decisions, acting as a bridge between the control plane (routing protocols) and the data plane (BIER forwarding).

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If a flag bit is added to routing protocol messages to identify user side nodes, then correct packet forwarding to user side nodes is achieved, but protocol message structure complexity increases

Engineering Contradiction:
Improveuser side node identification accuracyVSAvoidprotocol message structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent uses a simple parameter change (adding a single flag bit) rather than a complex structural modification. This minimal parameter addition provides the necessary identification capability while keeping the protocol message structure as simple as possible, thereby limiting the increase in device complexity.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent segments the routing message into distinct functional parts, with the flag bit serving as a separate identification component. This segmentation allows the flag bit to be added independently without affecting other parts of the protocol message structure, making the system easier to implement and maintain despite the added complexity.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3605974B1Information transfer methods and devices
Publication Date: 2024.07.03 ZTE CORP
  • EP3605974B1 patent drawingFigure 1~2
  • EP3605974B1 patent drawingFigure 3~4
  • EP3605974B1 patent drawingFigure 5~6

AI summary

Disclosed in the present application are an information transfer method and device. When a user side node sends a traffic request through a MLD, IGMP or PIM protocol or sends prefix information through routing protocols such as Babel, BGP, OSPF, ISIS and the like, a forwarding side node can clearly know by a manner of adding a user side mark whether the user side node is connected to the forwarding node. When performing forwarding according to a BIER rule, the forwarding side node can identify the user side node and encapsulate a packet to have a correct destination address to be sent, so as to ensure that the user side node can correctly receive a traffic message.