1. A method for filtering network packets, the method comprising: receiving, with the network traffic appliance, a data string associated with one or more of the network packets and identifying one or more keywords in the data string; iteratively examining, with the network traffic appliance, the one or more keywords in the data string against at least one rule keyword associated with each of a plurality of rules to determine whether the one or more keywords matches at least a portion of the at least one rule keyword for each of the plurality of rules, wherein each of the plurality of rules represents one or more network access policies; updating, with the network traffic appliance, a counter associated with each of the plurality of rules for each of the one or more keywords that matches the at least a portion of the at least one rule keyword associated with each of the plurality of rules; determining, with a network traffic appliance, whether the updated counter associated with each of the plurality of rules is equal to a preset matched keyword value for each of the plurality of rules; writing, with the network traffic appliance, one or more of the plurality of rules into a list of satisfied rules associated with the data string when it is determined that the updated counter associated with the one or more of the plurality of rules is equal to the preset matched keyword value for the one or more of the plurality of rules; and determining, with the network traffic appliance, whether to grant access of the one or more network packets to at least one server based on the list of satisfied rules.