Censorship resistance

如今的社群媒體格局高度集中。絕大多數使用者都集中在少數幾個平臺上，例如 Facebook、Reddit 或 Twitter。這些平臺都是由大型企業經營，而這些企業受制於獲利動機和美國法律。近年來，這些平台越來越多地審查使用者和整個社群，而且審查的理由往往令人質疑。受此影響的使用者自然會尋求替代方案。本文旨在幫助使用者進行評估。

For this purpose we will consider as censorship anything that prevents a person from expressing their opinion, regardless of any moral considerations. All the options explained here also have legitimate uses, such as deleting spam. Nevertheless it is important for users to understand why their posts are getting removed and how to avoid it.

The first and most common source of censorship in this sense is the admin of a given Lemmy instance. Due to the way federation works, an admin has complete control over their instance, and can arbitrarily delete content or ban users. The moderation log helps to provide transparency into such actions.

The second source of censorship is through legal means. This often happens for copyright violation, but can also be used for other cases. What usually happens in this case is that the instance admin receives a takedown notice from the hosting provider or domain registrar. If the targeted content is not removed within a few days, the site gets taken down. The only way to avoid this is to choose the hosting company and country carefully, and avoid those which might consider the content as illegal.

Another way to censor is through social pressure on admins. This can range from spamming reports for unwanted content, to public posts from influential community members demanding to take certain content down. Such pressure can keep mounting for days or weeks, making it seem like everyone supports these demands. But in fact it is often nothing more than a vocal minority. It is the task of admins to gauge the true opinion of their community. Community members should also push back if a minority tries to impose its views on everyone else.

All of this shows that it is relatively easy to censor a single Lemmy instance. Even a group of instances can be censored if they share the same admin team, hosting infrastructure or country. Here it is important that an admin can only censor content on their own instance, or communities which are hosted on his instance. Other instances will be unaffected. So if there is a problem with censorship, it can always be solved by using a different Lemmy instance, or creating a new one.

But what if the goal was to censor the entire Lemmy network? This is inherently difficult because there is no single entity which has control over all instances. The closest thing to such an entity are the developers, because they can make changes to the code that all the instances run. For example, developers could decide to implement a hardcoded block for certain domains, so that they can't federate anymore. However, changes need to be released and then installed by instance admins. Those who are affected would have no reason to upgrade. And because the code is open source, they could publish a forked software version without these blocks. So the effect would be very limited, but it would split the project and result in loss of reputation for the developers. This is probably the reason why it has never happened on any Fediverse platform.

最後，利用軟體漏洞進行全網審查的可能性依然存在。試想一下，如果 Lemmy 或其底層軟體堆疊中存在漏洞，攻擊者可以刪除任意內容。如果使用頻率不高，這種漏洞可能暫時不被發現，但過一段時間後肯定會被發現。經驗表明，開源軟體中此類嚴重缺陷的修復速度非常快。此外，多個不同的 Fediverse 平台同時存在嚴重漏洞的可能性也極低。

總結來說，避免 Lemmy 受到審查的最佳方式，是透過眾多獨立實例的存在。這些實例應由不同的管理員維護、使用不同的代管服務商，並位於不同的國家。此外，使用者應關注開發進程，留意是否出現可能導致所有實例產生中心化控制點的變動。根據上述說明，顯而易見地，在 Lemmy 上進行審查非常困難，且總是有辦法規避。這與中心化平台形成鮮明對比。