OpenNSL API Guide and Reference Manual
Field Processor APIs

The OpenNSL field module provides access to Field Processor features. The field processor can be used to classify packets based on predefined protocol fields from Layer 2 through Layer 7, as well as user-defined protocol fields. Based on these classifications, various actions can be taken, such as:

Each Field Processor entry is allocated in a particular group. Each group is capable of matching packets based on a particular set of qualifying attributes referred to as a qset.