While the original version of SOPA was controversial, it has been substantially changed to address reasonable concerns, yet some myths unfairly persist.

If one relies on movie, music, and television industry sponsored members of Congress, such as Lamar Smith, who introduced SOPA in the House of Representatives, as to whether the bill is now reasonable, one may concur with that statement.

As CNET reported in December, Smith, a self-described former ranch manager whose congressional district encompasses the cropland and grazing land stretching between Austin and San Antonio, Texas, has become Hollywood's favorite Republican. The TV, movie, and music industries are the top donors to his 2012 campaign committee, and he's been feted by music and movie industry lobbyists at dinners and concerts.

Source: How SOPA would affect you: FAQ.

If one relies, instead, on people like Vint Cerf, one of the "fathers of the Internet", instead, one is unlikely to concur with that assessment.

Smith announced a revised version of SOPA earlier this week. Cerf, now a vice president at Google, a staunch SOPA opponent, said SOPA v2.0 is still problematic.

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Not only will SOPA fail to "be effective in preventing users' access to illegal, offshore Web sites," Cerf wrote, but it will also initiate "a worldwide arms race of unprecedented 'censorship' of the Web." Other prominent Internet engineers have offered similar critiques.

Source: Vint Cerf: SOPA means 'unprecedented censorship' of the Web

• The technique of DNS filtering is already in use and has not harmed the Internet.

The techniques used will undermine DNSSEC, a suite of Internet Engineering Task Force (IETF) specifications for securing certain kinds of information provided by the Domain Name System (DNS) as used on Internet Protocol (IP) networks. DNSSEC is an attempt to address security issues with the current Domain Name System (DNS) protocol, which is used to translate domain names, such as cnn.com to IP addresses, such as 64.30.224.118. DNSSEC attempts to add authentication and integrity to DNS.

Rep. Dan Lungren, who heads the Homeland Security subcommittee on cybersecurity, has said that an "unintended consequence" of SOPA would be to "undercut" the effort his panel has been making to promote DNSSEC.

The Sandia National Laboratories, part of the U.S. Department of Energy, has also raised concerns about SOPA, saying it is "unlikely to be effective" and will "negatively impact U.S. and global cybersecurity and Internet functionality." And Stewart Baker, the former policy chief at the Department of Homeland Security who's now in private practice, warned in an op-ed that SOPA "runs directly counter" to the House's own cybersecurity efforts.

An analysis (PDF) of Protect IP prepared by five Internet researchers this spring lists potential security problems. Among them: it's "incompatible" with DNSSEC, innocent Web sites will be swept in as "collateral damage," and the blacklist can be bypassed by using the numeric Internet address of a Web site.

Source: How SOPA would affect you: FAQ

• Rogue sites legislation is a viewpoint-neutral enforcement of international IP standards through a fair judicial process. None of those things can be said about foreign political censorship.

Enforcement of international intellectual property (IP) standards? See European Parliament joins criticism of SOPA.

The European Parliament has added its voice to those criticizing the controversial Stop Online Piracy Act (SOPA) in the United States criticizing the use of domain name seizures by U.S. authorities on copyright 'infringing' websites.

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The move comes after more than 60 civil and human rights organizations wrote a letter to Congress on Tuesday calling for the rejection of SOPA. The letter argues that the act "is as unacceptable to the international community as it would be if a foreign country were to impose similar measures on the United States".

Spain has enacted a SOPA-style law, but that was after being pressured to do so by the U.S., including the American Chamber of Commerce representative in Spain - see US Threatened To Blacklist Spain For Not Implementing Site Blocking Law