Patterns for Application Firewalls

Enterprise applications are typically implemented as web applications and may use web services. This provides a flexible architecture suitable for B2B communication but it may introduce new security threats. This paper discusses here an analysis pattern for an Application Firewall, intended to protect the applications from some of these threats. They also present a pattern for an XML Firewall, a specialization of the Application Firewall, and used to filter the contents of XML documents.