Iraq, Memory Holes, SmartFilter and a whole lot more

The Memory Hole blog reports that it is blocked on U.S. military computers. An email from a user stationed in Iraq to the Memory Hole shows that this block page information is shown to the user when they try to access the site:

Access Denied (content_filter_denied)
Your request was denied because of its content categorization: “Extreme;Politics/Religion”
For assistance, contact your network support team.

The categorization indicates that it is probably blocked as a result of the sites categorization as “Extreme” by a commercial filtering application rather than a specific blockage by the U.S. military. But you never know. A quick google search reveals…

that the text “content_filter_denied” is somehow associated with BlueCoat. BlueCoat sells proxy appliances that can be configured for content filtering using URL databases from Secure Computing (Smartfilter), SurfControl and Websense. A check in these databases reveals that is categorized as:

Surf Control: is in our list and categorized as Violence

Category: News and Media


4.0 List
List Date: Fri May 28 (SN: 131)

3.x Premier
List Date: Fri May 28 (SN: 4341)

3.x Standard
List Date: Fri May 28 (SN: 549)

No exact match of “Extreme;Politics/Religion”. However, a quick check of the BlueCoat website shows that the U.S. Airforce purchases BlueCoat devices equiped with SmartFilter. Interesting.

Additional sources confirm this; some even contain letters from outraged military users. (See “We don’t need Big Brother on the Net” and “Public notification is common courtesy”.) Furthermore, this document (dated 15 April 2004) indicates that BlueCoat appliances configured with SmartFilter 3.0 are in use by the U.S. Air Force. (This document puts the price for Sidewinder w/ SmartFilter at $1,078,000.00., other interesting software in there includes Network Associates Sniffer Pro.)

In addition to the Air Force, the Army apparently also uses Smart Filter, in fact you can buy it here.

Back to the blocking….

The facts indicate that is blocked, most likely by a BlueCoat appliance configured with SmartFilter 3.0. But the site is not classified as “Extreme;Politics/Religion” but simply “Politics/Religion”? The most likeley explanation is that the military is filtering the “Extreme” category and not using to the most recent version of the SmartFilter database. At some point the Memory Hole was probably doubly classified as Extreme and Politics/Religion and, if the military has not updated their blocking lists, is blocked by the military as a result.

However, should your “mission requirements dictate” that you have access to a web site blocked by SmartFilter you can always use the handy “Request for SmartFilter (Internet) Exemption” for available here (archived pdf) to get access, “for official use only” of course.


  1. SmartFilter is a product of cobion, which was purchased by ISS.

    If you test at you get the Category “Spam URLs”

  2. Nice work!

    One more documentation

    U.S. Army Switches to Secure Computing SmartFilter Software as Global Web Filtering Standard,03.htm

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