Ethernet Segment Substitution for Fast EVPN Convergence
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing EVPN interworking with ERP experiences traffic slow convergence and congestion due to MAC entry invalidation and lack of efficient switchover mechanisms, particularly in single-homed configurations, leading to prolonged traffic interruptions during link failures and recoveries.
Innovation Solution
Advertising the relationship of ES withdrawal and its substitution to other PEs, allowing for immediate update of next-hop adjacencies for MAC entries, thereby facilitating fast convergence of traffic without invalidating all MAC entries, and advertising ES reachability with substitution information to revert traffic routes efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If MAC entries are invalidated when Ethernet segment fails, then network reliability is improved by preventing traffic to failed segment, but traffic convergence speed deteriorates due to MAC entry relearning delay
Solution Approach 1:
The patent applies preliminary action by pre-configuring substitution Ethernet segments and pre-populating MAC entries with next-hop adjacencies before failure occurs. When a failure is detected, the system immediately switches traffic to the pre-prepared substitution segment without waiting for MAC entry relearning, thus resolving the contradiction between reliability and convergence speed.
Solution Approach 2:
The substitution Ethernet segment acts as an intermediary mechanism between the failed segment and the active traffic paths. Instead of directly invalidating MAC entries and waiting for relearning, the system uses the substitution segment as a bridge to redirect traffic immediately, maintaining both reliability and fast convergence.
2Stability of the object's composition
If all MAC entries are invalidated during Ethernet segment failure, then network stability is improved by removing incorrect routes, but productivity deteriorates due to traffic interruption and congestion
Solution Approach 1:
The patent segments the MAC entry management by separating valid MAC entries from those needing invalidation. Instead of invalidating all MAC entries, it selectively maintains valid entries and only removes/updates entries associated with the failed Ethernet segment, thus preserving network stability while minimizing traffic interruption and maintaining productivity.
Solution Approach 2:
The patent applies local quality by making differentiated handling of MAC entries based on their association with specific Ethernet segments. Valid MAC entries for operational segments are preserved, while only the local MAC entries tied to the failed segment are invalidated or updated, balancing stability requirements with productivity needs.
3Device complexity
If Ethernet segment withdrawal is advertised without substitution information, then protocol simplicity is maintained, but loss of time increases due to waiting for MAC entry aging
Solution Approach 1:
The patent applies preliminary action by pre-configuring substitution Ethernet segments and their associated MAC entries before any failure occurs. When withdrawal is advertised, the substitution information is immediately available to receiving nodes, eliminating the need to wait for MAC entry aging and significantly reducing traffic recovery time without substantially increasing protocol complexity.
Solution Approach 2:
The patent uses copying by creating duplicate MAC entries with next-hop adjacencies for the substitution Ethernet segment. These copied entries are pre-prepared and immediately activated when failure occurs, providing fast traffic recovery without requiring complex protocol changes or waiting for entry aging processes.
Data Source
AI summary
Embodiments of the present disclosure provide methods and apparatuses for network communication. A method comprises determining a link between an edge device of a second network and the first edge device of the first network is failed or the edge device of the second network is failed or an identifier of an Ethernet segment corresponding to the edge device of the second network has been changed; and advertising a first message including withdrawal of the Ethernet segment corresponding to the edge device of the second network and a corresponding substitution Ethernet segment of the second network, wherein the corresponding substitution Ethernet segment of the second network can be used by one or more other edge devices of the first network receiving the first message to switch routes associated with the Ethernet segment corresponding to the edge device of the second network to the corresponding substitution Ethernet segment of the second network.