"451 error" indicating the page erased by government censorship started

byBen Raynal

When viewing a web page,404 errorAnyone who is an Internet user should have experience with displaying HTTP error codes like " "404" is an error code indicating that the corresponding page has been deleted or the server has dropped, but as a new error code, there are "451 error"Was approved.

draft - ietf - httpbis - legally - restricted - status - 04
https://datatracker.ietf.org/doc/draft-ietf-httpbis-legally-restricted-status/


mnot's blog: Why 451?
https://www.mnot.net/blog/2015/12/18/451

Organizations that formulate standardization of Internet technologyInternet Engineering Task Force(IETF) has issued a "451 error" in the document indicating that "the page can not be accessed for legal reasons." According to Mr. Mnot's blog who was in charge of the document, the 451 error has already been activated and it is in a usable state.

I suggested a 451 errorOpen textTim Bray, co-founder of the company, "451" number is Ray Bradbury's "Fahrenheit 451 degreesIt comes from. "Similarly," there is no access right "is displayed as"403 ErrorThere is, "up to which" reason for whom access is prohibited "is not displayed. "451 error" was officially adopted as many people including Mr. Bray insisted on the importance of emphasizing the fact that censorship is being done on-line.

According to Mnot, the HTTP status code is restricted to 400 to 499Namespace, So it was argued whether it was appropriate to consume a limited number. Also, the introduction of a new status code potentially affects all resources, and if you display a message in the body with a header on the 403 error page, you can say "for whatever access is forbidden" From the beginning, it seems that there were many objections.

Bymike

On the other hand, some sites agreeing Tim's proposal began experimentally introducing 451 errors, and websites aimed at protecting legitimate online activitiesLumen, Webs that defend freedom of expression and informationArticle 19Have officially announced the 451 error because they began to show interest in the usefulness of being able to mechanically collect facts on web censorship due to 451 errors.

◆ "451 error" can be done, what can not be done
451 error does not guarantee that it will be used for all censorship content, but it can also be used with network based firewalls and web servers. Mnot predicted that Web sites like Github, Twitter, Facebook, and Google, which are forced to censor content, frequently adopt it. Also, in addition to being able to build a system that automatically tracks censorship as mentioned above, there is also a discussion in the community that encourages users to access content in different ways via 451 error.

Some governments may dismiss the use of the 451 error, but it is equally effective as it has the same meaning as sending a message to the citizen, "We are monitoring citizenship" That's it.