Egress Interface Selector for Network Switch Load Balancing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current communication systems face challenges in achieving optimal load balancing across multiple network paths, leading to inefficiencies in bandwidth utilization and potential packet reordering or remapping issues due to link failures or additions in network switches.

Innovation Solution

The implementation of an egress interface selector that uses a hash function to dynamically select network interfaces within a group of egress interfaces, managing a table to remap packet flows upon link failures and efficiently integrate new links, thereby maintaining balanced traffic distribution without disrupting existing flows.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a hash function is used to select network interfaces in a group of egress interfaces, then load balancing is improved and bandwidth utilization is optimized, but packet reordering or remapping issues may occur due to link failures or additions

Engineering Contradiction:
Improvebandwidth utilizationVSAvoidpacket delivery consistency
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent implements dynamic remapping of packet flows when link failures or additions occur. The egress interface selector continuously monitors the status of egress interfaces and dynamically adjusts the mapping between packet flows and available interfaces, ensuring that traffic is redistributed to healthy interfaces while maintaining load balancing through hash function calculations.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system incorporates feedback mechanisms by monitoring the operational status of egress interfaces and using this information to adjust flow remapping decisions. When interface status changes are detected, the system feeds this information back into the hash function calculation process to recalculate appropriate egress interface assignments, thereby maintaining reliable packet delivery despite network changes.

Inventive Principle:
Principle #23Feedback

2Reliability

If the egress interface selector dynamically remaps packet flows upon link failures, then network stability is maintained, but additional processing complexity is introduced

Engineering Contradiction:
Improvenetwork stabilityVSAvoidprocessing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent pre-calculates and stores hash function results for multiple potential egress interfaces before failures occur. When an interface failure is detected, the system can quickly switch to pre-computed alternative mappings rather than performing complex real-time calculations, thereby maintaining network stability while minimizing the processing overhead during failure events.

Inventive Principle:
Principle #10Preliminary action

3Adaptability or versatility

If new links are integrated into the egress interface group, then network capacity is expanded, but traffic distribution balance may be disrupted

Engineering Contradiction:
Improvenetwork expansion capabilityVSAvoidtraffic distribution balance
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

When new egress interfaces are added to the group, the system changes the parameters of the hash function calculation to incorporate the new interface indices. This ensures that the hash function distributes traffic evenly across the expanded set of interfaces, maintaining load balancing efficiency while adapting to the increased network capacity provided by the additional links.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3266166B1Method and apparatus for load balancing in network switches
Publication Date: 2021.11.17 MARVELL WORLD TRADE LTD
  • EP3266166B1 patent drawingFigure 1
  • EP3266166B1 patent drawingFigure 2A~2B
  • EP3266166B1 patent drawingFigure 3

AI summary

A forwarding engine in a network device selects one or more groups of multiple egress interfaces of the network device for forwarding packets received by the network device. An egress interface selector in the network device selects individual egress interfaces within the one or more groups selected by the forwarding engine. The egress interface selector includes a table associated with a first group of multiple egress interfaces, wherein elements in the table include values indicate individual egress interfaces in the first group. When the forwarding engine selects the first group, a table element selector of selects an element in the table to identify the individual egress interface for forwarding the packet.