Traffic Flow Matching
One of the essential features of an MPF is the granularity in which a security administrator
can inspect traffic flow. Class maps allow a security administrator to segregate the network
traffic flow within the network at the packet level. Each packet is identified for its content
and matched to attributes listed in the class map using the match command. The matched
traffic becomes a new traffic class. The class map representing the traffic class will then be
assigned to a policy map, which will apply actions (policies) to matched traffic. Creating a
class map requires two steps:
Step 1 Create a class map.
Step 2 Define class map matches.
Figure 8-1 illustrates how you can use class maps to inspect traffic flow.