MPLS Label Switching Router Backup Path Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In MPLS networks, existing solutions lack effective mechanisms for maintaining LDP sessions and forwarding traffic through backup paths when primary paths fail, leading to potential session interruptions and data loss due to the lack of robust protection techniques for label distribution and routing.
Innovation Solution
Implementing a Targeted Hello protection mechanism and organizing MPLS forwarding tables into multiple levels to predefine and switch traffic between main and backup paths, ensuring continuous session maintenance and traffic diversion upon path failures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single primary path is used for traffic forwarding in MPLS networks, then the forwarding path is simple and easy to manage, but the network reliability deteriorates when the primary path fails
Solution Approach 1:
The patent pre-establishes backup LSPs before failures occur, configuring backup paths and maintaining LDP sessions in advance. When the primary LSP fails, the backup path is already ready and can be activated immediately without needing to establish new paths during the failure event.
Solution Approach 2:
The patent maintains LDP sessions for backup paths even before failures occur, keeping the backup forwarding state active and ready. This cushioning approach ensures that when the primary path fails, the backup path can immediately take over without session establishment delays, thus preventing service interruption.
2Reliability
If backup paths are pre-configured for all possible failures, then the network reliability improves, but the device complexity and resource consumption increase
Solution Approach 1:
The patent segments the forwarding table into multiple levels: the first level contains primary LSP forwarding information, while the second level contains backup LSP forwarding information. This segmentation allows the system to maintain backup paths without mixing them with primary path configuration, making the overall system more manageable despite the increased complexity.
Solution Approach 2:
The patent introduces a hierarchical dimension to the forwarding table structure by organizing it into multiple levels. Instead of a flat single-level table, the multi-level structure separates primary and backup path information into different hierarchical layers, enabling efficient access and management of backup paths without overwhelming the device with monolithic complexity.
3Speed
If LDP sessions are maintained for backup paths, then the traffic switching speed improves when primary paths fail, but the resource consumption increases
Solution Approach 1:
The system automatically maintains LDP sessions for backup paths and can self-activate them when primary paths fail. The patent implements automatic detection of primary path failures and seamless switching to backup paths without requiring manual intervention, allowing the network to serve itself during failure scenarios.
Data Source
AI summary
A label switching router (LSR) and a method of switching data traffic to a predefined backup traffic path by the LSR in an MPLS (multi-protocol label switching) network. The LSR, upon detection of failure of a protected path during an LDP session, maintains an LDP session and forwards data traffic via the backup traffic path according to a forwarding table. The forwarding table contains logical output interface information including an outgoing label, a logical output interface, and the next hop of the predefined backup path.