[Update 4:50pm EST: Verizon Wireless issued this statement: "Our network security system found traffic from some 4Chan Web sites that had strong potential to disrupt the Verizon Wireless network, affecting our customers' use of their services. With continuing investigation, and ensuring no current risk of harm, we are giving the green-light to all 4Chan traffic. We will continue to monitor for any possibility of network harm."  That "harm" was likely from another denial of service attack, and does not necessarily come from 4Chan themselves.  Malicious attackers can use false identifying information.  You can expect that company officials would strenuously avoid anything that could smack of a Net Neutrality violation at a time the issue remains a hot topic in DC.]

Last year, AT&T got itself into a political pickle over accusations that the provider had blocked access to 4Chan, an often controversial no-holds-barred imageboard.  With Net Neutrality a front burner topic, the accusation ran away in the press and heralded considerable finger-pointing about a major provider blocking access to a website they supposedly didn’t like.

Now it’s Verizon Wireless’ turn.  Over the weekend, 4Chan’s founder, Christopher Poole, claimed the wireless company was blocking access to the site:

Over the past 72 hours, we’ve been receiving reports from Verizon Wireless customers having difficulty accessing the image boards. After investigating, we found that Verizon is dropping traffic to/from boards.4chan.org, only on port 80 (HTTP). No other subdomain/IP/port is affected, which leads us to believe this block is intentional. A call was placed to their support staff last night, and we were told that the ticket would not be looked at until Monday at the earliest, and: “You’ll need the customer to call to request it be unblocked…”

Note: Users with mobile browsers that proxy (BlackBerry, Opera) won’t necessarily have issues accessing the boards.

Late Sunday evening, Poole claims he confirmed Verizon is intentionally blocking 4Chan:

After an hour and a half on the phone, we’ve received confirmation from Verizon’s Network Repair Bureau (NRB) that we are “explicitly blocked.”

Poole’s notice included Verizon’s phone numbers, giving members of the 4Chan community a place to vent, and that is precisely what has been happening all morning.  The Network Repair Bureau’s phone lines melted down, and the company claims it has not discovered precisely why the site is being blocked.

Before the inevitable outrage against Verizon Wireless commences, a few points to consider:

1. The AT&T incident a year ago was not an effort to block 4Chan’s site, just stop a denial of service attack originating from IP addresses connected to img.4chan.org.
2. A “block” does not necessarily mean an executive at Verizon Wireless specifically ordered the company to stop providing access to a particular site.  Blocks can be an automatic network management technique to control a traffic problem or denial of service attack, a technical error, or a problem external to Verizon itself.
3. I am a Verizon Wireless customer and have no problem reaching boards.4chan.com on my LG Chocolate phone.
4. Customers of Verizon FiOS or Verizon DSL are not blocked.

It seems prudent to wait a few hours to learn whether this is a poster child for Net Neutrality, or simply a technical issue.