CUSP Reliability

A controller generates service data based on information (such as interface information) reported by a forwarder and then delivers the service data to the forwarder through a control channel. To minimize service interruptions caused by a CUSP connection or controller fault, CUSP supports the following reliability solutions.

**Table 1** CUSP reliability solutions
Reliability Solution	Usage Scenario
CUSP connection reliability	This solution is used in CUSP connection fault scenarios. The controller backs up data. Before a CUSP connection is reestablished, the controller uses the backup data to process services, which ensures the continuity of services that have been generated on the controller after connection reestablishment.

CUSP Connection Reliability

The CUSP connection reliability solution backs up collected forwarder interface information, bindings between the controller's logical interfaces and the forwarder's physical interfaces, and the forwarder's connection management information. The data is used to implement controller service functions.

In CUSP connection fault scenarios, CUSP connection reliability is implemented as follows:

Before a CUSP connection is reestablished, the controller uses the backed up data to process services.
After the CUSP connection is reestablished, the controller re-collects forwarder information and updates original information to ensure that services are properly processed.