Adtran MX2800 M13 User Manual

Page of 200
7-2    
61200290L1-1G
Section 7, Circuit and Network Redundancy
MX2800 M13 Multiplexer User Manual
NOTE
In this mode, the DS3 must be connected to the 
IN
 and 
OUT
 jacks for
DS3 A.
3. CIRCUIT FAILURE RECOVERY MODE
In Circuit Failure Recovery Mode, two controller cards are installed with an incoming single DS3 line. See 
on page 7-2. In this mode, the MX2800 can continue operating in the event of a controller card 
failure. When both cards are healthy, the primary card actively processes data while the secondary card 
stands by and is ready to take over if the first fails. The secondary card continuously monitors the line and 
remains framed to the incoming signal. 
NOTE
During a card switch, service interruption occurs on both the DS3 and the
DSX1 connections. However, since the secondary controller card remains
framed to the incoming signal at all times, it is a minimal interruption.
 
Figure 7-2.  Circuit Failure Recovery Mode
See 
 for a list of this mode’s configuration requirements.
 
Table 7-1.  Configuration Requirements for Circuit Recovery
Selection Path
Recommended Setting
Config > Network Interface > XCV Threshold
1E-3 
*
Config > Network Interface > Network Protection
Disabled
Config > Network Interface > Max. Switch Threshold
3