Which additional configuration is required for NetFlow to provide traceback information?

Cisco Express Forwarding (CEF) is a fundamental, high-performance IP forwarding mechanism that NetFlow relies on, but it is a prerequisite for NetFlow operation itself, not an additional configuration specifically for obtaining traceback information.

To gather specific 'traceback information' with NetFlow, you need to identify and isolate particular traffic flows of interest. A classification ACL allows the engineer to define granular filtering criteria, ensuring NetFlow analyzes and exports data only for the specific traffic types targeted for traceback, such as from an anomalous source or to a specific destination.

The BGP routing process is responsible for exchanging routing information between autonomous systems, but starting it is not an additional configuration specifically required for NetFlow to provide traceback information; NetFlow collects flow data irrespective of the routing protocol.

LLDP (Link Layer Discovery Protocol) is a Layer 2 protocol used for discovering neighbor device information and has no direct role in NetFlow data collection, analysis, or the generation of traceback information.