Methods and systems for processing application-level content of network service protocols are described. According to one embodiment, a firewall maintains multiple configuration schemes, each defining a set of administrator-configurable content filtering process settings. The firewall also maintains a security policy database including multiple firewall security policies. At least one of the firewall security policies includes an associated configuration scheme and an action to take with respect to a particular network session based on a set of source Internet Protocol (IP) addresses, a set of destination IP addresses and/or a network service protocol. Policy-based content filtering of network sessions is performed by: (i) identifying a firewall security policy matching traffic associated with the network session; (ii) identifying content filtering processes to be performed on the traffic based on the configuration scheme associated with the matching firewall security policy; and (iii) applying the identified content filtering processes to the traffic.