Social media sites like Facebook and YouTube are now typically accessed over HTTPS, the encryption protocol used to protect online banking sessions and user logins for services of all kinds on the web.
By enabling the Barracuda Web Filter to decrypt, inspect and re-encrypt web traffic at the URL level, administrators have fine grained control over the use of web-based applications. This allows administrators to choose to block certain portions of web based applications such as Facebook Chat and Facebook Sharing, while enabling other portions, such as the rest of Facebook. Since Facebook, Twitter, various search engines such as Google, and many web-based applications run over HTTPS, SSL Inspection is required for this level of monitoring and blocking. With this control the administrator can define what they deem permissible on their network and need not block all of Facebook, Twitter, Google Apps and other popular web-based applications.
Additionally, since block pages cannot always be served when just using HTTPS filtering, using SSL Inspection almost guarantees presentation of a block page when needed.
See the notes for (1) and (2) below.
(1) In TransparentMode, you cannot configure domains or categories. If you currently use ProxyMode for inspection and are switching to TransparentMode inspection, any domains or categories you have specified for SSL Inspection are DISABLED. If you switch back to Proxy Mode inspection, domains and categories are restored.
(2) In TransparentMode, you can configure domains, not categories. Test SSL Inspection with a few domains to ensure system performance is satisfactory. If you currently use Proxy Mode inspection and are switching to TransparentMode inspection, any categories you have specified for SSL Inspection are DISABLED. If you switch back to Proxy Mode inspection, categories are restored. To prevent system overload, after switching to Transparent Mode inspection, you cannot add more domains.
Note that the Barracuda Web Filter Vx virtual machine 610 and higher only supports Proxy Mode inspection, including adding domains and categories.
With SSL Inspection, the content of a URL over HTTPS can be scanned. This allows the Barracuda Web Filter to apply policies and detect malware and viruses at the URL level.
The Barracuda Web Filter acts as a secure intermediary between user HTTPS web requests and the destination web server (i.e. Facebook.com, YouTube.com, yourdomain.com, etc.). HTTPS content in user web requests is decrypted and scanned by the Barracuda Web Filter, which then detects malware and enforces web policies configured on the BLOCK/ACCEPT pages. After processing, this HTTPS traffic will be re-encrypted on the fly by the Barracuda Web Filter and routed to the destination web server as shown in Figure 1.
Figure 1: SSL Inspection
To use this feature, the administrator installs a root certificate in client browsers from the Barracuda Web Filter. The Barracuda Web Filter can then intercept and inspect the HTTPS connections by presenting the client a CA derived from this root CA. If you have a high availability deployment, you must install the same root certificate on each Barracuda Web Filter.
If you only need to block by domain and/or domain (content) categories, you can enable HTTPS filtering on the 210 and higher. See HTTPS Filtering With the Barracuda Web Filter for details. Unlike SSL Inspection, HTTPS filtering does not decrypt the encrypted portion of URLs. This prevents monitoring or capturing of social media interactions such as chat, comments, shares, etc. HTTPS Filtering is a good choice when:
Popular for schools. Allow access to web-based email applications, but prevent potentially dangerous uploads and downloads.