Cisco Cisco Web Security Appliance S360 User Guide

Overview of Data Security and External DLP Policies, page 13-1

Managing Upload Requests, page 13-2

The Web Security appliance secures your data by providing the following capabilities:

When the Web Proxy receives an upload request, it compares the request to the Data Security and 
External DLP Policy groups to determine which policy group to apply. If both types of policies are 
configured, it compares the request to Cisco IronPort Data Security Policies before external DLP 
Policies. After it assigns the request to a policy group, it compares the request to the policy group’s 
configured control settings to determine what to do with the request. How you configure the appliance 
to handle upload requests depends on the policy group type. 

Upload requests that try to upload files with a size of zero (0) bytes are not evaluated against Cisco 
IronPort Data Security or External DLP Policies.

Cisco IronPort Data Security 
Filters

The Cisco IronPort Data Security Filters on the Web Security appliance 
evaluate data leaving the network over HTTP, HTTPS and FTP.

Third party data loss 
prevention (DLP) integration

The Web Security appliance integrates with leading third party 
content-aware DLP systems that identify and protect sensitive data. The 
Web Proxy uses the Internet Content Adaptation Protocol (ICAP) which 
allows proxy servers to offload content scanning to external systems