Sub-ring Network Routing for Fast Packet Failure Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for managing traffic forwarding in packet networks, particularly in mesh topologies, face challenges in achieving fast failure recovery times comparable to physical layer transport technologies like SONET/SDH, while maintaining loop freeness and complexity is high.
Innovation Solution
Implementing a sub-ring network with topologically diverse ring spans between end nodes in a mesh network, using a ring network routing scheme for high-speed protection switching and guaranteed loop freeness, allowing for fast failure recovery by propagating Failure Indication Messages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Spanning Tree Protocol is used to compute traffic forwarding paths through a mesh network, then loops are prevented, but failure recovery time increases to several seconds in large mesh networks
Solution Approach 1:
The patent segments the mesh network into multiple virtual rings, each with its own protection mechanism. By dividing the network into smaller manageable units (virtual rings), the system can perform localized protection switching without requiring full network-wide spanning tree recomputation, thus reducing failure recovery time while maintaining loop prevention through structured virtual ring management
Solution Approach 2:
The patent pre-establishes protection paths and virtual ring structures before failures occur. By pre-computing alternative paths and organizing network topology into virtual rings in advance, the system can immediately switch to protection paths upon failure detection without waiting for reactive spanning tree recomputation, achieving fast recovery while maintaining loop-free operation
2Loss of time
If two or more topologically diverse trees are computed for protection switching, then failure recovery time is reduced, but device complexity increases due to computation of large number of trees
Solution Approach 1:
Instead of computing multiple spanning trees from root nodes (traditional approach), the patent inverts the approach by organizing the network into virtual rings where protection paths are naturally defined by the ring structure itself. This inversion simplifies the computation from complex multi-tree algorithms to simpler ring-based path management, reducing device complexity while maintaining fast protection switching
Solution Approach 2:
The patent changes the fundamental parameter from tree-based topology to ring-based virtual topology. By transforming the network representation from spanning trees to virtual rings, the system achieves fast protection switching through ring reversal mechanisms rather than complex tree recomputation, significantly reducing computational complexity while maintaining rapid failure recovery
3Ease of operation
If conventional Ethernet flooding and MAC learning are used in mesh networks, then operation is simplified, but loop formation occurs during failure recovery
Solution Approach 1:
The patent pre-organizes the mesh network into virtual ring structures with defined protection paths before failures occur. By establishing this structured topology in advance, conventional Ethernet flooding and MAC learning can operate within the constrained virtual ring framework without forming loops, even during failure recovery, thus maintaining both operational simplicity and loop-free operation
Solution Approach 2:
The virtual ring structure acts as an intermediary layer between conventional Ethernet flooding and the underlying mesh topology. This intermediary structure provides the necessary constraints and path definitions that prevent loop formation while allowing standard Ethernet operations to proceed unchanged, thus maintaining ease of operation while ensuring reliability
Data Source
Figure 1a~1b
Figure 2~3
Figure 4a~4b
AI summary
A system for controlling packet forwarding through a point-to-point (p2p) connection between first and second end nodes of a packet network domain having a mesh topology. The system comprises a sub-ring network instantiated in the network domain, the sub-ring network comprising a pair of topologically diverse ring spans extending between the first and second end nodes. Each of the end nodes is controlled to forward packets of the p2p connection through the sub-ring network in accordance with a ring network routing scheme, and an intermediate node traversed by one of the ring spans is controlled to forward packets of the p2p connection through the ring span in accordance with a linear path routing scheme.