Understanding Convergence

Recall that convergence involves four primary activities: update, invalid, holddown, and flush. These activities come into play any time a router experiences a change in its routing table, including when the router is powered on. This section includes a scenario that shows the process of convergence by causing RouterC to cease sending routing updates to RouterA. This section also introduces the concept of parallel paths in a routing table and discusses some of the issues they can create.

Parallel Paths

When a router has two or more routes to the same network with the same metric, these routes can be thought of as having an equal cost. The term parallel paths is a just a common way to refer to occurrences of equal-cost ...

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