SRLG-Disjoint Network Routing via Graph Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining routing paths in communication networks, especially optical networks, fail to adequately account for shared risk of link failures and physical attributes, leading to inefficiencies in path disjointness and cost optimization.
Innovation Solution
The method involves defining a graph representing the network, assigning shared risk of link failure costs to edges, and identifying primary and backup paths while removing edges that share failure risks, along with constructing replacement nodes to ensure node disjointness and minimizing administrative costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional graph routing techniques are used, then routing paths can be determined based on basic graph theory, but they fail to account for shared risk of link failures and physical attributes leading to inadequate path disjointness
Solution Approach 1:
The patent segments the network graph into multiple residual graphs by removing edges that share common risk groups. This segmentation allows the routing algorithm to systematically explore disjoint paths while accounting for shared failure risks, transforming the single graph problem into multiple subgraph problems that can be solved independently and systematically.
Solution Approach 2:
The patent performs preliminary actions by pre-processing the network graph to identify and remove edges sharing common risk groups before executing the routing algorithm. This preliminary classification of edges by risk groups enables the subsequent routing process to automatically generate SRLG-disjoint paths without requiring complex real-time analysis during path computation.
2Productivity
If paths are selected to minimize administrative costs, then routing efficiency improves, but the resilience to failures may be compromised
Solution Approach 1:
The patent implements a dynamic routing approach where the residual graph is progressively modified based on both cost metrics and risk group constraints. The algorithm dynamically adjusts the search space by removing edges with shared risks while maintaining cost optimization, allowing the routing process to adaptively balance between administrative costs and failure resilience based on the specific network configuration and constraints.
3Reliability
If node disjointness is enforced, then routing reliability improves, but the number of valid paths decreases and computational complexity increases
Solution Approach 1:
The patent introduces replacement nodes as intermediaries to handle node disjointness requirements. When a node is removed from the residual graph to enforce disjointness, replacement nodes are introduced to maintain the graph structure and provide alternative routing options. This intermediary mechanism preserves node disjointness while minimizing the impact on overall path availability and reducing computational complexity.
Data Source
AI summary
A number of techniques are described for routing methods that improve resistance to faults affecting groups of links subject to common risks. One of these techniques accounts for failure potentials in physical networks by considering shared risk link groups separately from performance and costs metrics in determining a primary routing path and a backup path. A shared risk link group (SRLG) is an attribute attached to a link to identify edges that have physical links in common and can therefore be simultaneously disrupted due to a single fault. Another technique considers node disjointness and provides a solution of two paths that are as node disjoint as possible and minimizes administrative costs. The techniques may further be combined in a priority order thereby providing a solution of at least two paths that are strictly SRLG disjoint, as node-disjoint as possible, and have minimum administrative costs. Due to the priority order of evaluation and typical network physical configurations of links, with the links associated common fault SRLGs, the priority ordering technique is very efficient in determining at least two paths for routing between a source and destination node.