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Censorship The Internet Politics

HTTP Error Code 451 Approved For Censored Web Pages ( 141

An anonymous reader writes: The Internet Engineering Steering Group (IESG) has finally approved the new 451 status code for HTTP error messages involving web pages which have been repressed or removed for legal or political reasons. The initiative was proposed in 2013, and gained interest from various groups, such as Lumen (formerly Chilling Effects), who see the potential of the Bradbury-inspired code to help develop comprehensive indexes of censorship on the internet. Mark Nottingham, chair the IETF HTTP Working Group, says, "It'll be an RFC after some work by the RFC Editor and a few more process bits, but effectively you can start using it now."
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HTTP Error Code 451 Approved For Censored Web Pages

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  • 451 (Score:3, Funny)

    by pushing-robot ( 1037830 ) on Monday December 21, 2015 @12:07PM (#51158971)


    • Re:451 (Score:5, Funny)

      by Moof123 ( 1292134 ) on Monday December 21, 2015 @12:55PM (#51159349)

      Should have been "Error 1984 Big Brother Disapproves"

      • by Anonymous Coward

        Read other comments. "451" is more appropriate for censorship; leave 1984 for tracking...

        BTW, if you didn't recognize 415, perhaps they've won. :-(

        • Re:451 (Score:5, Insightful)

          by fuzzyfuzzyfungus ( 1223518 ) on Monday December 21, 2015 @01:49PM (#51159827) Journal
          Arguably, the correct code for 1984-style censorship is either a 404 or a 200 that returns a page full of historically corrected and party approved content.

          The honest censor is the one who says "yup, this exists and you can't see it." The effective censor is the one who successfully conceals the existence of whatever they are trying to keep you away from.
          • by doccus ( 2020662 )

            The effective censor is the one who successfully conceals the existence of whatever they are trying to keep you away from.

            Yup there's a lot of that about.. or not ;-) Hard to tell. Problem is you can't just google "stuff they're not telling me and not letting me know even exists". Weapons research is a perfect example. They don't just hide how these ultra advanced directed energy devices etc. work.. they hide their very existence. From us.. that is.. the citizens. Certainly not from the other side. They meake absolutely SURE that the enemy knows about their existence. Not much deterrant factor otherwise.But can't let the popu

        • by doccus ( 2020662 )

          What kind of sick sense of humor could they have to actually approve 451 as the code? It's like acknowledging that it'a repressive censorship and yet boasting about it at the same time...

      • by keko ( 1010009 )
        I assume this needs to be enforced at the ISP level or something. Nobody is going to return those 451s themselves. How long until we get a proxy-based search engine for all the censored content on the internet?
        • by Anonymous Coward

          Actually, search engines could start using it right now. The HTML they'd serve as the HTTP entity would say something like "I'd show you this page but some silly government requires it to be blocked because of a suspect bit of legal reasoning."

          • by kmoser ( 1469707 )

            Actually, search engines could start using it right now. The HTML they'd serve as the HTTP entity would say something like "I'd show you this page but some silly government requires it to be blocked because of a suspect bit of legal reasoning."

            If they really had a conscience, they'd serve the error code along with the actual blocked content, and let the user-agent simply decline to show it.

        • Re:451 (Score:5, Interesting)

          by UnknownSoldier ( 67820 ) on Monday December 21, 2015 @04:23PM (#51161011)

          > How long until we get a proxy-based search engine for all the censored content on the internet?

          Don't we already have part of this?

          The problem is we still have idiots who think censorship is the solution. Censor is precisely part of the problem:

          Only cowards censor.

          Certain people censor they are too insecure to discuss something rationally and too afraid of other people's propaganda that they think ignoring the problem will make it go away.

          Ignoring a problem doesn't make it go away.

          While the 451 is a "cute" solution, it is not really address the root problem.

        • If you get a DMCA takedown notice for something you have the rights to, but not the money to defend yourself, you might return a 451 instead of a 404 when it's removed/hidden.

          • by keko ( 1010009 )

            Depends on the context, I guess. You can just shut the offending content down.

            How is Google going to treat index scores in websites with 451s? Most people may want it completely removed without a trace.

            • Google generally supports the reporting of censorship - even their own web search results include links to when a search result is removed due to a DMCA request. It's likely that they would increase the rank of web sites being transparent about censorship.

              Shutting the offending content down normally returns 404. You can still display the same 404-style error page but with a 451 HTTP header, or you can provide details on the removal of the content. It doesn't really matter as the conte

              • by keko ( 1010009 )
                Maybe you're right, if every player sticks to the spec rules for this. Sticking to the rules and censorship usually don't go together, though.
            • This isn't going to do anything for a National Security Letter or anything along those lines. Returning 451 might be subtle but it definitely won't get you out of trouble if it's discovered - so it's in no way a true canary. The only safe canary is something where inaction reveals that something was compromised. This is for when you're allowed to tell the visitor exactly why. And it also standardizes reporting in such a way that automated tools connecting to the content can make an intelligent decision

      • Error 1984: Historical Inaccuracies Corrected

    • Re:451 (Score:5, Funny)

      by radarskiy ( 2874255 ) on Monday December 21, 2015 @01:19PM (#51159567)

      451: Halt and Catch FIre

  • by deodiaus2 ( 980169 ) on Monday December 21, 2015 @12:12PM (#51159013)
    Use 451 for legal reasons,
    Use code 452 for political ones.
    And a citation of what particular stature is being offended.
    • Re: (Score:2, Insightful)

      Law is political

      • Law is political

        I believe GP was wanting to differentiate between stuff that's banned by law for obvious reasons (child pr0n, malware, etc), and stuff that's banned by a legal body due to purely political/speech reasons (e.g. calling one's national governmental leader a poop-eating doody-head).

        • by donscarletti ( 569232 ) on Monday December 21, 2015 @02:26PM (#51160123)

          No, you and he are making the distinction between laws that you like and laws that you don't like.

          I agree that many laws, like the laws against child porn and malware are good. However if we tolerate the notion that these are not political issues since they are stemming from the natural order of things, then we must tolerate that to others, that the list of natural apolitical issues may be broader than they are to you and banning other things is not a political issue either. There is not a regime on earth that bans things that it does not consider harmful to the people. Remember that.

          • There is not a regime on earth that bans things that it does not consider harmful to the people. Remember that.

            False. In the US, for example, bans can and are enacted when local governments decide that something needs to be banned, even though the federal government says it shall not be. Case in point: Abortion. The federal government decided in Roe v. Wade that a woman's right to opt for an abortion is protected, meaning that the procedure cannot be banned at the state level. Yet it is effectively banned in most states of the former Confederacy, because those state legislatures enacted laws making it practical

            • Southern regimes consider abortion to be harmful to fetus (or as they would say: baby), woman and society. Thus, no-matter what federal courts say, they will do their darnedest to ban it. Federal rulings do have effect on the state level, but states still more or less rule themselves as they see fit (as per the US constitution). Thus, southern states are regimes that only ban things that they consider harmful to the people.

              I thought someone might bring up something like North Korea. But Dixie? Too easy!

        • by bentcd ( 690786 )

          The distinction can't really be drawn. In Germany it is considered harmful to deny the Holocaust to the extent that it's illegal to do so. If a German Google employee is left to decide whether such a ban is 451 or 452 he will likely conclude differently than a US Google employee would.

          And of course, child porn means different things in different countries. In some places, someone drawing a basic stick figure and writing underneath "naked child" may be guilty of creating child porn. How obviously harmful is

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      That is pointless. For those cases governments do not want information revealed, the censorship demand will come with a gag order forbidding to even tell that it is being censored. In these cases this code cannot be used.

      Therefor such a code only has value in a state based on justice and integrity where the rule of law is generally accepted and respected. Ironically this is a state least likely in need of such a code.

    • I would set the HTTP response's ETag [] to the offending content ROT13'd, but that's just me.

    • Error DMCA

  • Next HTTP status 205: Present, but spam, trojan or other irrelevant content.

  • Wecome to Nazi Germany!

  • christ who cares. (Score:3, Interesting)

    by nimbius ( 983462 ) on Monday December 21, 2015 @12:20PM (#51159071) Homepage
    not since the april fools teapot code has something so silly been proposed. from TFA:

    the 403 status code says "Forbidden", but it doesn't say "I can't show you that for legal reasons."

    because 403 is relaying constraints affected upon the target site path from the browsers configuration. "I cant show you that for legal reasons" is explained by blogs, chilling effects, boingboing, twitter, email, mailing lists, and sometimes even slashdot. keep your social web bullshit out of my nginx. all this code does is afford one more excuse for the user to stop investigating why or how this site was blocked. the new code isnt a redirect to information, and conveys nothing meaningful outside of boilerplating.

    By its nature, you can't guarantee that all attempts to censor content will be conveniently labeled by the censor.

    thats right. multinational corporations that dont want you reading about salmonella outbreaks and exploding recalls will not use 451. they will purchase an abundance of airtime on $news-website and then threaten any evidence of coverage with bankrupting the site. additionally your government isnt about to 451 your favourite e-zine that exposes the secret torture prison in cuba, theyll just null route that traffic. the FBI just hijacks your DNS and points it to their boilerplate eagle and shield jpg designed by a bureaucrat with all the comprehension of internet censorship as a four year old. Did your favourite website just get a gag order and secret court warrant? that sorry, 451 isnt going to show up because it would violate the conditions of the gag order. 451 is as useless as do not track, but social justice warriors love it.

    • > because 403 is relaying constraints affected upon the target site path from the -browsers configuration-

      Are you thinking of 406, which indicates the client (browser) configuration wouldn't accept the response?

      403 is access denied for -any- reason other than authentication failure. It could be the resource is only available 9:00 - 5:00 (business hours), it could be restricted by IP address, it could be available only to the 93rd caller. The server explicitly is not required to indicate why access has

    • by AmiMoJo ( 196126 )

      It's more a statement that censorship of this nature if considered and error condition, than a useful response code.

  • The tighter they close their fist the more webpages will slip from their grasp.

    Or something like that.

  • It is one thing for 'the man' to try and strangle society over being power hungry and a particularly foul individual that has difficulty qualifying as a human being, but for the dev's to play ball with this sickness by building framework is an outrage. Perhaps this is another 'gift' afforded by the H1B?

  • by Virtucon ( 127420 ) on Monday December 21, 2015 @12:56PM (#51159353)

    who see the potential of the Bradbury-inspired code to help develop comprehensive indexes of censorship on the internet

    So if I want to censor you and not have it tracked I'll just give you a 403 or a 500. Which is pretty much how it works now. This won't allow anybody to truly see how much censorship there is. What a waste of intellectual bandwidth.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      The point of this code is that it's a signal from the ISP or website holder to the user saying 'I'm sorry, I can't dish out this page because the government/corporation/the Bavarian Illuminati won't let me'.

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      So if I want to censor you and not have it tracked I'll just give you a 403 or a 500. Which is pretty much how it works now. This won't allow anybody to truly see how much censorship there is. What a waste of intellectual bandwidth.

      This is a wrong headed idea of how HTTP works. You make a request to a server and you get a response. One way of handling content removed because of censoring is to let it return 403, 404, or 500 or various other codes. By having a code that allows the server operator to return a

    • Hush! Politicians just may be dumb enough to say "good idea, let's use it!"

  • by kheldan ( 1460303 ) on Monday December 21, 2015 @01:19PM (#51159559) Journal
    I've been suspecting for quite some time now, but something like this makes it fairly obvious to me: The Internet is well on it's way to being more or less destroyed. I wouldn't at all be surprised if in the next 10 years or so, it gets literally fragmented to the point where it's just the 'U.S. Internet', and the 'PRC Internet', and the 'E.U. Internet', and the 'U.K. Internet', and so on, with no interconnection between the disparate networks, and before too much longer than that, no interoperability between them anyway. Oh well, it was fun while it lasted.
    • It's not going to be destroyed, it's going to fragment An anonymous network full of crap, a trust network that requires positive ID to post anything, a pay-to-play network with much higher bandwidth, etc. The darknet already exists, doesn't it? The internet becomes a William Gibson-esque dystopian future, but it doesn't go away. Isolationism is the inevitable future, whether due to infectious disease or terrorism, it's going to happen. Enjoy the everyone-to-everyone connection you have now, while you still
      • It's not going to be destroyed, it's going to fragment

        That's my entire point; 'fragmenting' == 'destoying it'.

        Enjoy the everyone-to-everyone connection you have now, while you still can.

        I don't have that; so-called 'social media' is one of the aggressive cancers that is killing the Internet, and I refuse to participate in the destruction of something that once was beautiful.

        The darknet already exists, doesn't it?

        Sure it does.. for now. Like Tor, it only exists because the powers-that-be allow it to exist, for their own purposes; once those purposes become obsolete, Tor will become anathema, and anyone using it will be considered a criminal.

        Want some advice, friend? Vote

    • I think you mean the "Facebook internet" and the "Google internet" and the "Microsoft Internet" and the "Baidu internet." All the companies want the Internet to turn into Cable TV 2.0, with them in control.

      • Maybe. And just like when it was AOL and all the other 'walled gardens' back in the day, I'll just ignore it and move on to something else. Maybe there'll be a grass-roots movement to start a wireless mesh network, and anyone who wanted the Internet to remain what it was originally will move to that instead. Maybe it'll all just become a useless, tangled mess of a walled garden like you imply, and I'll just walk away from it and go read more books instead, or (gasp, scandalous!) actually talk to more people
  • by Locke2005 ( 849178 ) on Monday December 21, 2015 @01:24PM (#51159619)
    Obvious Ray Bradbury tribute is obvious. Ray was a great author, he deserves it.
  • Could we use this when my local corporate firewall blocks a page? It would be great if apps recognized that. Sometimes, an application goes to download a file or register something, and instead of getting a file with the expected result, it gets back HTML with something like "This page was blocked... click OK to accept and continue" which obviously the application doesn't know to do. But if it got a 451, I can at least know what happened and possibly do something about it.

  • Ironically... (Score:4, Insightful)

    by Etcetera ( 14711 ) on Monday December 21, 2015 @01:37PM (#51159735) Homepage

    This appropriateness of this code is based around an interpretation of the novel that the creator doesn't share:

    “Useless,” Bradbury says. “They stuff you with so much useless information, you feel full.” He bristles when others tell him what his stories mean, and once walked out of a class at UCLA where students insisted his book was about government censorship. He’s now bucking the widespread conventional wisdom with a video clip on his Web site (, titled “Bradbury on censorship/television. []

    • Re:Ironically... (Score:4, Insightful)

      by Moof123 ( 1292134 ) on Monday December 21, 2015 @02:25PM (#51160109)

      I read the article you linked, and frankly it left me scratching my head. I think he managed to write a book about censorship unintentionally, as it was the only way to get to his real point about the perils of television. When I read the book I found the whole picture walls thing to be secondary rather than primary. Maybe he pulled a Homer?

      It would be like finding Orwell's diary and finding out he thought 1984 was about the perils of video cameras rather than government control, propaganda, and surveillance (to badly simplify).

  • by Anonymous Coward

    Terence Eden's Blog There is no HTTP code for censorship (but perhaps there should be) [] where Tim Bray announced the Internet-Draft proposal.

    I hope that they finally amend it to include the
    451 Unavailable for Legal Reasons of Resource magnet:?xt=urn:ed2k:354B15E68FB8F36D7CD88FF94116CDC1&xl=10826029


  • by WaffleMonster ( 969671 ) on Monday December 21, 2015 @01:48PM (#51159821)

    Remember seeing this back at the beginning of 2013. Why does it take three years for one single solitary status code to be "approved"? There sure as heck was not continuous ongoing work or discussion commensurate with the delay.

    I often get the distinct impression nobody including authors actually care about documents they are working on.

  • After my local Gubberment uses their version of lead-pipe cryptography to convince me that I should take down a website (as opposed to an all-expense paid vacation at the local PITA joint), do I really believe I can get away with putting up a marker that says "Not my fault - they made me!"

    Isn't this the same brand of crap as asking website managers to implement a web canary in their HTML? I thought we'd all already discussed that here and concluded that as wonderful as it sounds, it also sounds like a gre

  • Using a 4xx response says that it's the requester's fault for making a bad request. It should be a 5xx error because the provider is at fault for withholding information.

    • by Anonymous Coward

      It is the requestor's fault that they looked for censored data. Their request was "bad" but a few weeks at a reeducation facility should help.

    • Perhaps, but 410 (gone) and 403 (forbidden) are similar in nature.

      Mainly though, it's because people like the Ray Bradbury reference.
      • by allo ( 1728082 )

        410 is similiar, because you cannot know it. 403 is just correct, because you could probably know, if you're allowed to access something. i.e. /cgi-bin/ should be known to be inaccessible.

        OTOH you're not obliged to know, whats censored. It's even the other way round, most governments want you not to know, what's censored. So it's not your error to access the ressource.

    • Compare to 404. It's not found - the user did go to an invalid address. It's just that 451 is a little more specific on why it's not found.

      • by allo ( 1728082 )

        nope. Typing the wrong url is your fault.

        • Not if the URL used to be valid but no longer exists (Hey, just like 451). Technically, 410 is more correct, but 404 is what's used in common practice.

          • by allo ( 1728082 )

            yeah, no longer available would be 410, where the 4 is kind of wrong. It should be more like 2xx with the information "correct, but gone".

            • Oh. Now I get it. Your brand of linguistic pedantry doesn't even accept the RFC, even while trying to use their numbering scheme. You're over-simplifying 4xx a bit if you say it's just "user error."

              2xx is used when the client's request was successfully received, understood, and accepted. []. In the case of a missing page, only the first two of the three are satisfied. You can't accept a request and successfully respond if the content is not there. Success is defined by the retrieval of the content, not the

              • by allo ( 1728082 )

                Personally i think 410 does not fit both 4 and 5. 2 would be an option in the sence, as it was received and understood (no question?) and accepted (but with the response "nothing here anymore"). But it does not fit the intention, that the client wanted to retrieve something and failed in it.

                Put it another way: If the client says "give me the contents of this box", is giving him nothing when the box is empty an "Okay" response, but he is probably not satisfied with it.

                • You're missing what their definition of "accepted" is. And it is entirely based around whether the content retrieval is successful. Otherwise, you really have almost no use for 4xx at all.

    • by GuB-42 ( 2483988 )

      This is a user error in a sense that the server is perfectly configured and the user agent (the browser) asked for a resource that it isn't allowed to access.
      A 5xx means that something is not working as intended on the server (software bug, network problem, unsupported feature,...).
      The distinction is a purely technical one between a http client and a http server. Not between a human user and provider.

      It is the same reason why you get a 404 when your browser follows a dead link. At a human level, the provide

      • That may be the theory. In practice, the majority of 403 errors you'll encounter are due to server software bugs creating permissions problems.

    • Isn't it more along the lines of '4xx: it's a feature' and '5xx: it's a bug?'

      Besides, this is just an extension of '403 Forbidden.'

  • by U2xhc2hkb3QgU3Vja3M ( 4212163 ) on Monday December 21, 2015 @03:12PM (#51160431)

    A lot of comments have referenced about it but nobody's linked to it yet: []

  • I think it would be useful to also specify a header with thich the server (or proxy) can tell the user agent the scope of the block. Mainly so that the user can know it the block can be circunvented by using a proxy or not.

  • by sinij ( 911942 ) on Monday December 21, 2015 @03:30PM (#51160591)
    Ray Bradbury Fahrenheit 451 []
  • Censorship, or rather, repression of information of any kind is a danger to freedom and therefore a danger to our civilized society. It always reminds me of one of the quotes in SMAC:

    "As the Americans learned so painfully in Earth's final century, free flow of information is the only safeguard against tyranny. The once-chained people whose leaders at last lose their grip on information flow will soon burst with freedom and vitality, but the free nation gradually constricting its grip on public discourse has

  • 4xx means client error. 5xx means server error. we need 6xx for government error.

Life in the state of nature is solitary, poor, nasty, brutish, and short. - Thomas Hobbes, Leviathan