CANOGA PERKINS 2361 T1 Modem - Manual (Page 57)

The EdgeAccess Universal Chassis System
2361 Modem Users Manual 7-1
Chapter 7
Redundant Configurations
For critical circuits where downtime cannot be tolerated, redundant configurations are used. In a
redundant configuration a secondary (inactive), circuit is ready to begin transmitting data. Should
there be a problem on the active circuit. For example, if the system detects loss of signal, the
secondary circuit will take over the actual data payload. Personnel can freely troubleshoot the
problem without disrupting data transmission.
To ensure that the inactive circuit is truly ready to begin transmitting data at any time, a data
stream is continually sent through the inactive modem, and its error rate is continually tested.
There are two types of redundancy:
Fiber Path Redundancy: Allows two pairs of fibers to be connected to the optional redundant
OLIM, as shown in Figure 42. Notice these OLIMs each have two
pairs of Tx and Rx connectors.
OLIM OLIM ELIM
ELIM
Primary Fiber
Pair
Secondary Fiber
Pair
T1 or E1 T1 or E1
Figure 41. Fiber Path Redundancy