A binary state machine system and method for REGEX processing of a data
stream in an intrusion detection system are disclosed. The method
comprises maintaining a state table. The state table is indexed such that
inputs comprising a current state and a current character yield an output
of a new state. The new state is related to an indication of an attack on
a computer network. The method further includes maintaining the current
state. An input stream comprising a plurality of characters is received. A
first character of the input stream is selected as the current character.
The current character and the current state are compared to the state
table to generate a new state.
