Local Congestion Mitigation
Local Congestion Mitigation (LCM) searches for congestion on a configurable cadence (as opposed to a triggered event). It provides localized mitigation recommendations in surrounding interfaces (local interface-level optimization) within a domain. LCM computes the shortest paths for one or more tactical policies to divert minimal traffic on a congested interface to alternate paths with sufficient bandwidth. It attempts to keep as much of the traffic on the original IGP path. With LCM, you can do the following:
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Monitor congestion as defined by the interface thresholds you specify.
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Visually preview LCM recommendations on your network before you decide whether to commit the Tactical Traffic Engineering (TTE) SR policy deployment.
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Enable LCM to delete any down, failed, or uncommitted LCM TTE policies when there is an imminent risk of network failures based on LCM solution configurations. For more information, see the advanced configuration options (Auto Repair Solution and Adjacency Hop Type) in Configure LCM.
LCM enables a wider application of the solution in different network topologies, including those with multiple IGP areas, because of its simpler path computation and limitation to specific network elements. Focusing on the problem locally within a domain eliminates the need to simulate edge-to-edge traffic flows in the network through a full traffic matrix. It allows for better scaling of large networks. Also, LCM collects TTE SR policy and interface counters via SNMP and does not require SR-TM.
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Take a look at the Example: Mitigate congestion on local interfaces to see how to use LCM in your network. |