7-4 61204659L1-1ASection 7, Circuit and Network Redundancy MX2800 STS-1 User ManualCircuit and Network Failure Recovery ModeNOTEThe XCV Threshold settings are based on the error rates consideredacceptable on the STS-1 or DS-1 before switching.3. CIRCUIT AND NETWORK FAILURE RECOVERY MODEIn this mode, two controller cards are installed and connected to two individual STS-1 lines. This modeprovides full STS-1 redundancy. In this mode, the primary controller card is connected to the primarySTS-1 line and the secondary controller card is connected to the secondary STS-1 line. The primary cardand line actively transmit data, while the secondary card remains in standby. Should a failure occur ineither the controller card or the network, then a switchover occurs to the secondary card or network.The MX2800 STS-1 has the ability to internally re-route the network connection if a controller card andthe opposite network connection fail. For example, in Figure 7-3, failed NET A is connected to healthyCard A; and healthy NET B is connected to failed Card B. In such an instance, the MX2800 STS-1automatically re-routes NET B to Card A.NOTEThe configuration requirements (shown in Table 7-2 on page 3) for bothfailure recovery modes are identical with one exception. In Circuit andNetwork Failure Recovery mode, set the Network Protection to Enable.Figure 7-3. Circuit and Network Failure Recovery ModeMX2800STS-1Alternative route betweenAlternative route betweencards when Networkcards when NetworkProtection is EnabledProtection is Enabled
