Hitless Protection in Packet Switched Networks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Packet switched networks face challenges in providing reliable and uninterrupted service for traditional TDM services due to limitations in service availability and packet loss rates, hindering the transition from dedicated TDM networks to converged packet networks.
Innovation Solution
The implementation of a method and system for end-to-end hitless protection in packet switched networks, which involves creating non-overlapping working and protecting paths, replicating traffic, and using marker packets to ensure seamless switching and maintain service continuity by selecting packets from either path based on consistency checking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If packet switched networks are used to transport TDM services, then service flexibility and bandwidth efficiency are improved, but service availability and packet loss rate worsen
Solution Approach 1:
The network path is segmented into working path and protecting path, allowing independent operation and failure isolation. This segmentation enables the system to maintain service availability by switching to the protecting path when the working path fails, while still using packet switched networking for flexibility and efficiency.
Solution Approach 2:
The system changes the operational parameters by implementing hitless protection mechanisms including packet replication, sequence number tracking, and automatic path switching. These parameter changes enable packet switched networks to meet the reliability requirements for TDM services while maintaining their inherent flexibility.
2Quantity of substance
If packet switched networks are used to transport TDM services, then bandwidth efficiency is improved, but packet loss rate worsens
Solution Approach 1:
The system performs preliminary actions by replicating packets at the source and preparing both working and protecting paths before failures occur. This preliminary replication ensures that when packet loss is detected on one path, immediately available copies can be transmitted through the alternative path without actual data loss.
Solution Approach 2:
The invention uses packet copying/replication to create redundant copies of TDM traffic on both working and protecting paths. This copying mechanism ensures zero packet loss by having backup copies ready, while the packet switched network maintains bandwidth efficiency through efficient routing and resource utilization.
3Reliability
If working path and protecting path are implemented with non-overlapping routes, then reliability is improved, but device complexity increases
Solution Approach 1:
The system implements universal protection mechanisms that can be applied to multiple TDM service flows through standardized hitless protection protocols. The same working path and protecting path infrastructure serves multiple purposes, reducing overall network complexity while maintaining high reliability through non-overlapping physical routes.
Data Source
AI summary
A method and system are described for providing hitless protection in a packet switched network having source nodes and destination nodes. The method includes enabling a working path and a protecting path between the source and destination nodes. The working path is non-overlapping with respect to the protecting path. The method further includes replicating traffic in a given one of the source nodes to generate replicated traffic. The method also includes forwarding the traffic and the replicated traffic through a working path and a protecting path, respectively, from the given one of the source nodes to a particular one of the destination nodes. The method additionally includes delivering a hitless-protected service in the particular one of the destination nodes by selecting traffic packets received from either the working path or the protecting path.