Configuration example:
　　
　　
　　interface serial 5/0
　　ip route-cache flow
　　
　　
　　?If CEF not configured, Netflow enhances existing
　　switching path (i.e. optimum switching)
　　?If CEF configured, Netflow becomes a flow
　　information gatherer and feature acceleration tool
　　
　　Information eXPort:
　　Router to collector system
　　ip flow-export version 5 [origin-ASPeer-as]
　　ip flow-export destination x.x.x.x
　　
　　?Flow aggregation (new in 12.0S):
　　Router sends aggregate records to collector system
　　ip flow-aggregation cache asprefixdestsourceproto
　　
　　
　　enabled
　　export destination x.x.x.x