What are IP blocks?

Hi! I’m Rae, a Movement Communications Associate at the Wikimedia Foundation, and long-time Wikimedia volunteer. This post discusses IP blocks—what they are, why they are placed, and IP block exemptions.

On Wikimedia projects, rules for how each project works are defined by their editor community. They develop policies and guidelines¹ through consensus-building discussions.² This includes rules that govern conduct, like civility and conflict of interest policies, as well as content, like neutral point of view and verifiability guidelines. With the goal of implementing these policies and guidelines, communities elect volunteers that have additional technical access.

Communities elect administrators, who have tools that allow them to implement community consensus locally³ (on one wiki). They can delete and protect pages, block users and IP addresses from editing, and assign user groups, among other abilities.

Additionally, the global Wikimedia community elects users with the ability to implement community consensus on a broader scale: stewards.⁴ These users have tools that allow them to respond to cross-wiki needs, including by locking accounts, globally blocking IP addresses from editing, and assigning global groups.

IP blocks and collateral effects

Since anyone can edit Wikimedia projects, there are often many unconstructive edits. To respond to and prevent this, administrators have the ability to block users from making actions on a wiki. Blocks can be applied to either accounts, IP addresses, or IP ranges. And they are configurable: blocks can be of limited length or indefinite, users can be blocked from individual pages or namespaces (e.g., articles, or categories), or all editing in general. Other actions can also be prevented, including sending emails, creating other accounts, or editing their own talk page.⁵

Collateral effects

With accounts, it is generally clear that only one person will be affected by the block: the person who controls the account. With IP addresses, that is less clear. Multiple users could share the same IP address or range (a group of IP addresses often allocated together), which brings in the question of collateral effects.

Let’s imagine a scenario where three unrelated users (A, B, and C) are assigned by their internet service provider (ISP) to the same IP address. User A is an active contributor, about to start working on a new article. User B doesn’t edit but likes to read articles, and User C is interested in promoting their business.

If User C is blocked for promotional editing, the underlying IP might be subject to a 24-hour autoblock. This means that User A would be unable to edit from that IP address for the duration of the block. User B’s reading would be unaffected, as the block only prevents editing.

IPs are not great at identifying individual end-users. When users share IPs or an IP range,⁶ it can result in collateral effects, where innocent users are unintentionally blocked from editing because they happen to share an IP with an unconstructive user.

Are there alternatives to IP blocks?

Given the potential for collateral effects from IP blocks, it’s reasonable to ask why they’re even used. The short answer is that there are no good alternatives; blocks are the primary preventative anti-abuse measure available to Wikimedia communities.

Another preventative anti-abuse tool does exist, called AbuseFilter. Each edit on a wiki is checked against a set of rules before the edit goes through. These rules are defined in filters, which admins can create and edit.⁷ If a filter is “hit”, i.e., an edit was flagged by the filter’s ruleset, it can make actions like warning the user, tagging the edit, or disallowing the edit entirely, depending on how the filter was configured.

Filters are just a set of rules, and are as a result very limited. For example, you could define a filter that prevents edits which remove more than 5000 bytes of a page by users with 10 edits or less. The intent is clear: to prevent new users from blanking articles. However, this won’t affect users who have 11 edits doing the same, or from removing 4999 bytes of content. AbuseFilter does not use machine learning and is not itself adaptive, and thus is only useful for preventing very obvious vandalism that the rules can easily check for, without too many false positives.

Machine learning tools do exist for anti-abuse work, though they are primarily responsive. Many projects employ anti-vandalism bots that revert unconstructive edits (like ClueBot NG or SeroBOT) and machine learning models exist that can flag potentially damaging edits to volunteers.

These tools—AbuseFilter, anti-vandalism bots, and machine learning models—are not alternatives to blocks. Fundamentally, if a user is repeatedly contributing unconstructively, the only way to prevent their continued editing is to block their account or IP address.

Proxy blocks

There are two main types of IP blocks that may affect you. The first are normal blocks made in response to disruptive editing from other users on your IP address or range. The second are blocks of open proxies–shared IP addresses accessible anywhere through paid or free services. 

Proxies route users’ internet traffic through shared servers, allowing people to mask their individual connection behind a shared IP. Bad actors often use these proxies to evade blocks placed on their IPs or accounts. In the interest of preventing this abuse, open proxies have been blocked on Wikimedia projects since 2004.

That decision was made over 20 years ago. Since then, there have been significant changes in the types of proxies available and their ease of access. Through services like iCloud Private Relay and in-browser VPNs, many everyday internet users connect via proxy without knowing it. And peer-to-peer proxy networks, where traffic is routed through other users’ residential internet connections, mean that any IP address can act as a proxy.

Blocks of peer-to-peer proxy networks can often have more collateral than intended; in many countries with developing internet infrastructure, hundreds or even thousands of residential users might share the same single IP address. If a device using that IP address is also part of a peer-to-peer proxy network, and an outside user accesses it to disruptively edit Wikimedia projects, a block of that IP could have significant collateral effects.⁸

In an effort to reduce collateral effects, peer-to-peer proxies are no longer preemptively blocked globally.⁹ Individual projects, such as the English, Spanish, Farsi, and Chinese Wikipedias, also make proxy blocks locally which can include preemptive peer-to-peer proxy blocks.

Unblock and IP block exemption processes

Projects generally prefer not to unblock proxies and IPs that are being used disruptively. Instead, affected users can request local and/or global IP block exemptions (IPBE) for their account.

Local IPBE is given on a per-wiki basis, and exempts users from all IP blocks (local and global) while editing that particular project. Global IPBE is a global group and exempts users only from global blocks, though on all projects.

The specific process of requesting IPBE depends on:

1. Type of block
   • Is the IP blocked locally, globally, or both?
   • If both, or if the IP is blocked locally on multiple wikis, the user may need to request multiple IP block exemptions.
2. Proxy use
   • Is the IP blocked as a proxy, or for other reasons?
   • If a proxy, does the user have an approved reason to contribute through a proxy?
   • If not, the standard advice is to disable their VPN to contribute to Wikimedia projects.
3. Account status
   • Does the affected user have a registered account?
   • If not, they would need to request the creation of an account first, then IP block exemptions. This is because IP blocks generally prevent account creation.
4. Projects
   • Depending on the project’s local policies and guidelines, the process for requesting an IP block exemption may differ.

For users facing a local block, information about the local project’s appeals and exemptions processes are provided in the block message (which show up when a blocked user attempts to edit).

For users facing a global block, the stewards’ wizard provides information about the optimal process to contact.

Notes

1. This links to a Wikidata item, which lists the “Policies and Guidelines” pages of dozens of Wikimedia projects. In this post, I link to Wikidata items where no central page exists for a concept. ↩︎
2. Though some policies are global, like the Universal Code of Conduct, these are generally still enforced at the level of an individual project, in line with the subsidiarity principle. In the case of systemic failures of local projects to follow broader Wikimedia standards, other processes exist, like global RfCs and the U4C. ↩︎
3. “Local”, in the Wikimedia context, refers to a single Wikimedia project. “Global” refers to all Wikimedia projects. ↩︎
4. Also global rollbackers and global sysops, though they have a more limited toolset focused on supporting individual project cleanup/maintenance, does not include global actions. ↩︎
5. By default, blocked users can edit their own user talk page. This allows for them to appeal the block while not being able to edit the rest of the project. ↩︎
6. Very few IP allocations are static. The IP someone is using to connect to the internet can change throughout the week, day, or even hour, depending on their ISP. Even when IPs are changing, most ISPs limit those changes within a specific range. When there are disruptive edits being made on multiple IPs in an identifiable range of IPs, that range will generally be blocked. ↩︎
7. Each local wiki has their own set of abuse filters. There are also global filters which are active on every project except the English and Japanese Wikipedias, who have opted out. ↩︎
8. I explored the impact of peer-to-peer proxy blocks in a three-part Diff post series in December 2022. ↩︎
9. A ‘global IP block’ is technically distinct from a ‘local IP block’. Global blocks are applied by stewards and prevent editing from that IP on all Wikimedia projects. Local IP blocks prevent editing from that IP on a single Wikimedia project. A global IP block can be disabled by local administrators on a project, but that is uncommon. ↩︎