Director Installation and Configuration Guide
Pre-call routing is the process of routing a call before the call connects to a location. In pre-call mode, Interaction Director receives a call event from a SIP network interface, usually a telecommunications carrier. Interaction Director analyzes statistical data collected from managed CIC servers, then "directs" the carrier to send the call to a specific destination point.
You can think of pre-call routing as "carrier-based routing" since routing decisions occur before the call connects and are based on signaling information from the carrier network.
A signaling link from a network carrier sends advance notifications of incoming calls to Director. It receives this information, views the current state of all call centers, and then sends a notification back to the PSTN indicating where to route the call. Thus, the call routes before answering it.
Pre-call routing can reduce toll charges, since Director makes intelligent routing decisions before the call connects, rather than using post-call routing to transfer the call after sending it to a call center site.