URL based Content Filtering Using Trend Micro White Paper

[anurag007]

http://www.cisco.com/en/US/prod/coll...89-492776.html

The Cisco IOS® Content Filtering feature using Trend Micro infrastructure provides a mechanism to allow, block, or simply log web (HTTP Universal Resource Locator [URL]) requests going through the router. The filtering is based on categories configured in Cisco IOS Software such as gaming, pornography, weapons, etc. You can either block or permit more than 50 available categories in Cisco IOS Software. Whereas these categories are to improve employee productivity, another set of categories is to protect the network and resources: Security categories protect from adware, malware, spyware, and phishing sites.

When a client makes a HTTP request, the information is sent to the Trend Router Provisioning Server (TRPS). The TRPS sends back category information about the HTTP request. For example: games.yahoo.com belongs to the Gaming category. If Gaming is denied in the Cisco IOS Software policy, the router disallows the request (Figure 1).

You can configure black and white lists locally in Cisco IOS Software to permit and deny URLs and domains. If the Trend Micro server is unreachable, the router defaults to local available black and white lists. Content Filtering also supports local black and white lists that you can configure to either permit or deny URLs and domains. Cisco IOS Software supports 100 black and 100 white lists.

In order to reduce the latency of the future HTTP transactions and thus improve your experience, the router caches the categorization information received from the TRPS and uses this information to verify policy, instead of sending the URL categorization request to the TRPS.