Maintenance Manual

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Cisco ICM Enterprise Edition Administrator Guide Release 6.0(0)
Chapter 2 Fault Tolerance
Peripheral Gateways
Figure 2-6 NIC Fault Tolerance
In a duplexed environment, two NICs are on-line and handling routing requests
simultaneously. Typically, each NIC handles part of the total call routing load for
ICM software. The Synchronizers combine the two input streams to ensure that
both sides of the Central Controller receive the same routing requests. If one of
the NIC processes fails, or one side of the Central Controller is removed from
service, the signaling network detects that communication is no longer possible
to that NIC and automatically sends all routing requests to the remaining NIC
process.
Peripheral Gateways
Peripheral Gateways use a combination of the synchronization and hot standby
approaches to fault tolerance. The Open Peripheral Controller (OPC) operates as
a synchronized process pair on a duplexed PG system. The Peripheral Interface
Synchronizer Synchronizer
Central Controller
Side A
Central Controller
Side B
AT&T
NIC A
AT&T
NIC B
CallRouter CallRouter
Agent
Agent
Line Sharing
Unit
A-Links
ICRP, MCI, Nortel,
or Sprint NIC
Load Balanced
Portion of
Route Requests
Load Balanced
Portion of
Route Requests
Idle path
Active path
ICRP, MCI, Nortel,
or Sprint NIC
37352