Barracuda Networks Application Blocking

The Barracuda Web Filter is a complete content filtering and application blocking solution designed to enforce acceptable Internet usage policies by blocking access to objectionable content and unauthorized Internet applications. Through the ability to easily block or allow Internet applications, administrators have the power to better secure the network perimeter, limit bandwidth usage and eliminate unwanted communications.

Unlike pure HTTP proxy solutions, the Barracuda Web Filter enables customers to enforce policies governing usage of applications that access the Internet. In addition, The Barracuda Web Filter allows administrators to create exception policies for specific users and groups so they can override the blocking filters that prevent them from accessing content or applications.

The Barracuda Web Filter's Internet application blocking features include:

• Instant Messaging (IM) Blocking. The Barracuda Web Filter enables administrators to set policy governing usage of public IM clients, including AIM, ICQ, Yahoo! Messenger, and MSN Messenger. These public IM clients can not only provide means for unmonitored communications, but their security vulnerabilities are often the target of those in the hacking community. Blocking public IM communications outright is one strategy to secure information flow and increase network security.
• Application Blocking. In addition to IM applications, the Barracuda Web Filter includes policies for popular applications that access the Internet, including Internet music applications, software updaters, Skype and SkypeOut, and popular browser toolbars.
• IP and Port Blocking. Administrators can customize their own IP blocking policies based on any combination of source or destination network IP address ranges and ports. One common usage of this feature is to prevent compromised machines from accessing the Internet.

For most Internet applications, the Barracuda Web Filter can control applications efficiently by profiling the ports and destination IP addresses used by those applications. However, peer-to-peer applications such as Skype communicate with other peers at varied IP addresses rather than centralized servers, and they utilize a number of fallback ports that include commonly used ports for other protocols, including HTTP and HTTPS. To be able to perform application blocking on applications such as Skype, the Barracuda Web Filter utilizes real-time packet inspection technology to analyze protocols independent of their port or destination email server. By integrating the protocol analysis with policy controls, the Barracuda Web Filter enables control of peer-to-peer applications based on time range, user, group, or subnet.

This combination of Web and other Internet application blocking techniques enables administrators to define and implement complete Internet usage policies for their organization.