Bidirectional Network Fault Synchronization via AIS-RDI
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for fault synchronization in bidirectional data networks are resource-intensive, non-scalable, and require costly Bidirectional Forwarding Detection (BFD) protocols, which are not feasible for less sophisticated networks, and fail to propagate fault information upstream effectively.
Innovation Solution
The method involves transmitting a second Alarm Indication Signal (AIS) with Remote Defect Indication (RDI) from a downstream endpoint to an upstream endpoint, using Interface Identifier and Global Identifier TLVs, enabling event-based fault synchronization without relying on BFD, and allowing for end-to-end failure coordination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If BFD protocol is used for fault synchronization, then fault detection capability is improved, but resource usage and cost increase significantly
Solution Approach 1:
The patent extracts the fault notification function from the resource-intensive BFD protocol and implements it using the existing AIS message framework. By taking out only the essential fault indication capability and embedding it in AIS messages with FLI and RDI elements, the system achieves fault detection without requiring full BFD protocol overhead, thus reducing resource consumption while maintaining detection capability.
Solution Approach 2:
The patent creates a simplified copy of the fault notification mechanism by using AIS messages that contain FLI (Fault Location Information) and RDI (Remote Defect Indication) elements. Instead of implementing the complete BFD protocol, the system copies only the necessary fault indication functionality into the existing AIS framework, making it lightweight and suitable for networks without BFD capability.
2Loss of information
If BFD protocol is deployed for fault notification, then upstream fault information propagation is improved, but scalability deteriorates
Solution Approach 1:
The patent makes the AIS message framework universal by enabling it to carry both traditional alarm information and new fault location information (FLI) and remote defect indication (RDI) elements. This multi-functional approach allows the same message structure to serve both conventional alarm purposes and upstream fault notification purposes, eliminating the need for separate BFD protocol deployments and improving scalability across diverse network configurations.
Solution Approach 2:
Instead of using BFD to notify upstream endpoints of faults (the conventional approach), the patent inverts the notification direction by enabling downstream endpoints to send AIS messages with RDI elements upstream. This reversal allows fault information to propagate in both directions using the existing AIS infrastructure, improving scalability without requiring bidirectional BFD sessions.
3Reliability
If continuous BFD monitoring is implemented, then live connectivity monitoring is improved, but resource consumption increases
Solution Approach 1:
The patent replaces continuous BFD monitoring with event-driven periodic action. Instead of maintaining constant BFD sessions for connectivity monitoring, the system uses periodic AIS message exchanges that are triggered by fault events. The FLI and RDI elements enable downstream endpoints to periodically report fault status upstream only when relevant events occur, reducing resource consumption while maintaining monitoring effectiveness.
Data Source
AI summary
Methods and apparatus for optimizing fault synchronization in a bidirectional data network are provided. In an example, a downstream endpoint of the data network receives a first Alarm Indication Signal (AIS). The first AIS indicates a first FLI of an upstream interface having an interface fault. The downstream endpoint transmits, to an upstream endpoint of the data network, a second AIS including a Remote Defect Indication (RDI) and a second FLI identifying the downstream endpoint. An upstream endpoint of the data network receives the second AIS and determines that the AIS is an AIS-RDI (AIS-RDI) from the presence of the second FLI. The presence of the AIS-RDI triggers the upstream endpoint to initiate tunnel failure synchronization with the downstream endpoint.