Cable TV and internet service provider Comcast recently rolled out an upgrade to its entire internet service network that prevents DNS blocking. DNS blocking would be necessary to enforce the Stop Online Piracy Act (SOPA) should it pass.

To summarize the proposed piece of legislation, SOPA gives both the U.S. government and copyright holders the authority to seek court orders against websites associated with infringing, pirating and/or counterfeiting intellectual property. If it becomes law, it could drastically change the way the Internet operates. For example, if a website is accused of containing copyright-infringing content (like a song, picture, video clip etc.), the site could be blocked by ISPs (like Comcast), de-indexed from search engines and even prevented from doing business online with services like PayPal.

The DNSSEC technology Comcast has implemented across its network is intended to add an extra layer of security to websites by checking for a special DNS signature to prove that the site is actually what it claims to be, according to a TechDirt report.

The humor in all of this is that Comcast is a big supporter of SOPA. But now it’s not only made its network incompatible with SOPA, it’s also undercut the need for SOPA somewhat by putting in place technology that helps legitimize the identity of websites to improve accountability and security.

I’m sure this will be brought up in detail when web security experts and tech business leaders testify about SOPA and PIPA to a congressional committee next week.

For more information about the proposed legislation, check out VentureBeat’s ongoing SOPA coverage.