MX2800 STS-1 User Manual Circuit and Network Redundancy, Section 7Circuit Failure Recovery Mode61204659L1-1A 7-32. CIRCUIT FAILURE RECOVERY MODEIn Circuit Failure Recovery Mode (Figure 7-2), two controller cards are installed for a single STS-1 line.In this mode, the MX2800 STS-1 can continue operating in the event of a controller card failure. Whenboth cards are fully functional, the primary card actively processes data while the secondary card remainsin standby. The secondary card continuously monitors the line and remains framed to the incoming STS-1signal.Table 7-2 provides recommended settings for this mode.NOTEDuring a card switch, service interruption is experienced on both theSTS-1 and the DSX-1 connections. However, since the secondarycontroller card remains framed to the incoming STS-1 signal at all times,it is a minimal interruption.Figure 7-2. Circuit Failure Recovery ModeTable 7-2. Configuration Requirements for Circuit RecoverySelection Path Recommended SettingConfig > Network Interface > XCV Threshold 1E-3 (see the following note)Config > Network Interface > Network Protection DisabledConfig > Network Interface > Max. Switch Threshold 3Config > Network Interface > Min. Switching Period 10 secondsConfig > T1/E1 Interface > T1/E1 Circuit Protection Enable the T1/E1 channels to be considered for circuitredundancyConfig > T1/E1 Interface > XCV Threshold 1E-3 (see the following note)MX2800 STS-1
