Cisco Cisco Web Security Appliance S160 User Guide

similar to the Allow action for Cisco IronPort Data Security Policies in that the upload request will be 
compared to the Access Policies. The final action the Web Proxy takes on the request is determined by 
the applicable Access Policy.

Each client request is assigned to an Identity and then is evaluated against the other policy types to 
determine which policy group it belongs for each type. The Web Proxy evaluates upload requests against 
the Data Security and External DLP Policies. The Web Proxy applies the configured policy control 
settings to a client request based on the client request’s policy group membership.

To determine the policy group that a client request matches, the Web Proxy follows a specific process 
for matching the group membership criteria. It considers the following factors for group membership:

Identity. Each client request either matches an Identity, fails authentication and is granted guest 
access, or fails authentication and gets terminated. 

Authorized users. If the assigned Identity requires authentication, the user must be in the list of 
authorized users in the Data Security or External DLP Policy group to match the policy group. The 
list of authorized users can be any of the specified groups or users or can be guest users if the Identity 
allows guest access.

Advanced options. You can configure several advanced options for Data Security and External DLP 
Policy group membership. Some options (such as proxy port and URL category) can also be defined 
within the Identity. When an advanced option is configured in the Identity, it is not configurable in 
the Data Security or External DLP Policy group level.

The information in this section gives an overview of how the Web Proxy matches upload requests to both 
Data Security and External DLP Policy groups. 

The Web Proxy sequentially reads through each policy group in the policies table. It compares the upload 
request status to the membership criteria of the first policy group. If they match, the Web Proxy applies 
the policy settings of that policy group.

If they do not match, the Web Proxy compares the upload request to the next policy group. It continues 
this process until it matches the upload request to a user defined policy group. If it does not match a user 
defined policy group, it matches the global policy group. When the Web Proxy matches the upload 
request to a policy group or the global policy group, it applies the policy settings of that policy group.