Cisco Cisco Administrative Workstation Installation Guide

The ICM system needs highly reliable networks to ensure sufficient real-time 
responsiveness and fault tolerance. Because the ICM system is a mission-critical, 
fault-tolerant system, it must be able to respond quickly when a node goes off-line 
for any reason. Depending on the situation, the ICM system might need to switch 
communication paths or activate other nodes to keep the system running without 
interruption.

In addition to responding to node failures, the ICM system needs to perform 
diagnostics on failed nodes so they can be returned to service as soon as possible. 
Often, the ICM diagnostic procedures take place over a Wide Area Network 
(WAN).

The ICM system must also be able to respond to route requests from the 
Interexchange Carriers (IXCs) within a certain minimum time-out period. For 
example, the AT&T intelligent call processing network requires a response from 
the ICM system within 200 milliseconds of receiving a route request. In a 
geographically distributed ICM configuration, this means that the ICM system 
must perform communications between the NICs and CallRouters on both sides 
of the Central Controller and return a route response all within the 200 
millisecond time-out period.

This chapter helps you to prepare network facilities for an ICM system 
installation. In this chapter, complete the following tasks:

Determine requirements for visible and private networking. The ICM 
networks must meet certain minimum bandwidth and latency requirements.