Differential Path Routing for Sub-Flow Delay Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Private Line Emulation (PLE) protocols face challenges in managing differential delays across multiple paths in packet-switched networks, leading to out-of-sequence packet delivery and the need for expensive de-jitter buffer memory.
Innovation Solution
The method involves measuring delays on multiple paths, determining delay differences, and adjusting queue delays at network nodes to align path delays with a target delay, thereby compensating for differential delays without requiring large de-jitter buffer memories.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If traffic flow is split across multiple smaller capacity paths, then routing flexibility and network utilization are improved, but differential delay among paths increases causing out-of-sequence packet delivery
Solution Approach 1:
The patent measures and records the delay characteristics of each path in advance before actual traffic flow is transmitted. These pre-measured delay values are stored and used to determine appropriate buffer depths for each path, allowing the system to proactively compensate for differential delays before they cause out-of-sequence delivery issues.
Solution Approach 2:
The patent introduces virtual buffer depths for each path based on pre-measured delay characteristics. These virtual buffers act as a cushion to absorb the differential delay variations among multiple paths, ensuring that packets from different paths are reassembled in the correct sequence at the destination without requiring excessively large physical buffers.
2Manufacturing precision
If large de-jitter buffer memory is allocated to compensate for differential delay, then packet reordering accuracy is improved, but memory cost and device complexity increase
Solution Approach 1:
The patent assigns different virtual buffer depths to different paths based on their specific delay characteristics. Instead of uniformly allocating large buffer memory to all paths, each path receives a buffer depth tailored to its individual delay profile, optimizing memory utilization while maintaining packet reordering accuracy.
Solution Approach 2:
The patent transforms the physical buffer depth parameter into a virtual buffer depth parameter that can be dynamically adjusted based on measured delay characteristics. This allows the system to achieve the required packet reordering accuracy by modifying buffer depth parameters rather than allocating proportionally more physical memory resources.
3Adaptability or versatility
If path delays are not equalized, then network routing flexibility is maintained, but differential delay causes out-of-sequence packet delivery
Solution Approach 1:
The patent introduces virtual buffer depths as an intermediary mechanism between the diverse path delays and the packet reassembly process. These virtual buffers mediate the timing differences among multiple paths, allowing packets to be held temporarily in virtual buffer slots until their counterparts from other paths arrive, ensuring reliable in-sequence reassembly without constraining path selection.
Data Source
AI summary
A method is provided to compensate for differential delay among a plurality of paths between first and second nodes in a network. The method may involve measuring delay for each of the plurality of paths for a plurality of sub-flows transmitted between the first node and the second node on respective paths of the plurality of paths. The plurality of sub-flows are obtained by splitting a traffic flow. The method involves determining delay differences among the delay for each of the plurality of paths, and adjusting, based on the delay differences, a queue delay associated with a respective flow of the plurality of sub-flows on one or more of the plurality of paths to achieve a path delay that is equal to a target path delay for each of the plurality of paths.