3.4 Dynamically Controlled Routing

DCR is a routing system controlled by a centralized Network Processor (NP) that provides to the switches an alternative path recommendation for traffic in a network.

Physically, a switch connects to the processor via a dedicated data link. The switches format and send to the Network Processor (NP) information concerning the CPU loading, the number of idle trunk groups between destinations, the number of calls overflowed from a direct path, and the number of incoming calls from other switches.

On the basis of DCR algorithm, the NP determines the most safe and idle alternative path for calls that overflow from direct route.

The Network Processor (NP) will provide to the switch this recommendation during update cycle. This update cycle includes the transport of the traffic data from the switch, the processing time on the NP, and the transport of the recommendations into the routing tables on the switch.