Static routes are used within many IES services. Unlike dynamic routing protocols, there is no way to change the state of routes based on availability information for the associated CPE. CPE connectivity check adds flexibility so that unavailable destinations are removed from the service provider routing tables dynamically and minimize wasted bandwidth.
The availability of the far-end static route is monitored through periodic polling. The polling period is configured. If the poll fails a specified number of sequential polls, the static route is marked as inactive.
An ICMP ping mechanism is used to test the connectivity. If the connectivity check fails and the static route is de-activated, the router continues to send polls and reactivate any routes that are restored.