Ring Rapid Spanning Tree Protocol Hardware BPDU Forwarding

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional spanning tree protocols face challenges in achieving sub-millisecond re-convergence times due to software processing delays, which increase with the number of nodes in a network, and are not compatible with proprietary protocols like EAPS, limiting their effectiveness in maintaining loop-free topologies and efficient communication.

Innovation Solution

The Ring Rapid Spanning Tree Protocol (RRSTP) utilizes hardware to forward proprietary Bridge Protocol Data Units (BPDUs) within a ring topology, ensuring sub-50 ms re-convergence while maintaining compatibility with RSTP and other spanning tree protocols, allowing for bi-directional transmission and configuration of forwarding tables to manage traffic efficiently.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional spanning tree protocols use software processing to handle BPDUs, then protocol compatibility is maintained, but re-convergence time increases significantly (10-50 milliseconds or more)

Engineering Contradiction:

Improveprotocol compatibilityVSAvoidre-convergence time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent replaces software-based BPDU processing with hardware-based processing. The spanning tree protocol processing is moved from the software layer to the hardware layer, allowing BPDUs to be processed and forwarded in microseconds rather than milliseconds, while maintaining compatibility with standard BPDU formats and protocols.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a hardware intermediary component that sits between the network interface and the software processing layer. This hardware component pre-processes BPDUs, performing critical spanning tree operations in hardware before software needs to intervene, thus reducing the software processing burden and acceleration convergence.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Adaptability or versatility

If the number of nodes in the network increases, then network coverage and functionality improve, but software processing time for BPDUs increases dramatically

Engineering Contradiction:

Improvenetwork scalabilityVSAvoidBPDU processing time

Core Design Contradiction:

Adaptability or versatilityVSLoss of time

Solution Approach 1:

By implementing spanning tree protocol processing in hardware, the patent eliminates the bottleneck of software processing that scales poorly with network size. Hardware processing provides consistent microsecond-latency regardless of the number of nodes, enabling the network to scale without proportionally increasing convergence time.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Loss of time

If hardware is used to forward BPDUs for rapid convergence, then re-convergence time decreases to sub-millisecond levels, but compatibility with conventional protocols and proprietary protocols like EAPS is limited

Engineering Contradiction:

Improvere-convergence timeVSAvoidprotocol compatibility

Core Design Contradiction:

Loss of timeVSAdaptability or versatility

Solution Approach 1:

The patent designs the hardware processing component to be protocol-agnostic, supporting multiple spanning tree protocols (STP, RSTP, MSTP) and proprietary protocols like EAPS through a unified hardware architecture. The hardware can be configured to handle different protocol types while maintaining rapid convergence performance.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent enables dynamic configuration of hardware processing parameters to adapt to different protocol requirements. By changing hardware processing modes and parameters, the system can optimize for different protocol types while maintaining sub-millisecond convergence times across all supported protocols.

Inventive Principle:

Principle #35Parameter changes

4Reliability

If software processes each BPDU before forwarding, then protocol compliance is ensured, but the convergence process becomes slower compared to hardware transit time

Engineering Contradiction:

Improveprotocol complianceVSAvoidconvergence speed

Core Design Contradiction:

ReliabilityVSSpeed

Solution Approach 1:

The patent substitutes software-based BPDU processing with hardware-based processing. The hardware component performs protocol compliance checks and processing in parallel, maintaining protocol correctness while reducing processing time from milliseconds to microseconds, thereby ensuring both compliance and speed.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS7564779B2Ring rapid spanning tree protocol

Publication Date: 2009.07.21 ALCATEL-LUCENT USA LNC

AI summary

In a method for enabling facilitation of re-convergence, designation information for a first port of each one of a plurality of bridges in a multi-bridge ring is received and designation information for a second port of each one of a plurality of bridges in a multi-bridge ring is received. The first port of each one of a plurality of bridges is a first direction Ring Rapid Spanning Tree Protocol (RRSTP) port and the second port of each one of a plurality of bridges is a second direction RRSTP port. The first direction around the ring (e.g., a forward direction) is opposite the second direction around said ring (e.g., a backward direction). A first reserved MAC address is associated with the first direction port of each one of the bridges and a second reserved MAC address is associated with the second direction port of each one of the bridges.