Which QoS mechanism identifies traffic flows and uses DSCP, IP precedence, and MPLS EXP to assign priority levels?

Classification is the process of identifying and categorizing traffic flows based on various criteria, including source/destination IP addresses, port numbers, protocols, and QoS fields like DSCP, IP Precedence, and MPLS EXP. This initial step is crucial because it allows subsequent QoS mechanisms (like marking, policing, and queuing) to apply appropriate treatment to different traffic types. Without classification, QoS policies cannot differentiate between critical and non-critical traffic. Policing limits bandwidth, marking sets priority values, and queuing manages traffic congestion; all of these rely on prior classification.