While there is some cross-over, WebWasher and Sidewinder (McAfee Web Gateway and McAfee Firewall Enterprise as they are now both known) are completely separate products with different jobs on the network.
Sidewinder is a Firewall that can also perform tasks such category-based URL web filtering and anti-virus scanning. The Application Defense functionality, allows specific control of certain layer-7 application protocols (such as HTTP). Application Defenses are confgured using the Policy -> Defenses -> Application Defenses screen. These defenses are paired-toegther with a Generic application defense into a defense group which is then applied to the access control rule.
The application defense functionality on the Firewall product isn't the same as the overall functionality provided by WebWasher (Web Gateway). Web Gateway is a dedicated web security solution providing deep web access control, inspection, scanning and filtering. It is possible to control certain aspects of the HTTP protocol using an application defense definition, on the Firewall but you will not be able to control specific MIME types (application/x-shockwave-flash). This is one of the areas where the two products are completely different.
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