On freenode, the network which hosts the Wikimedia IRC channels, an IRC hostmask cloak replaces the display of your IP address or host name with a cloak. For example,
firstname.lastname@example.org could become
ajvol@wikimedia/Alexander-Sigachov in several IRC-related messages (
/whois, and various join/part/quit notifications, depending on the client of the person seeing the notification). Many people make use of cloaks because an exposed IP can often be considered sensitive and private information. Note that they have no effect on nicknames.
Purposes of a cloak 
- Verification on IRC: The primary reason to wear a cloak is to prove that you are the user on-wiki who you say you are on IRC. For example, jwales'
wikipedia/Jimbo-Walescloak shows that he is who he says he is, as you cannot add a fake cloak onto yourself.
- Community pride: According to Rob Levin, the late ex-head of freenode, user cloaks are a way to show off your pride as a Wikimedian to those who see you in other IRC channels, and are intended to help build a sense of community.
- Privacy: They are also a way to hide your hostname for security and privacy reasons. freenode provides an "unaffiliated" cloak to those without a cloak for a particular project. (Note: Unaffiliated cloaks will not hide hostnames for users using the webchat.freenode.net client. Project cloaks do work with webchat, and unaffiliated cloaks will work with other clients).
People who deal with Wikimedia cloaks 
- Dungodung (talk) (IRC nick
- Barras (talk) (IRC nick
- PeterSymonds (talk) (IRC nick
All cloaks must conform to the DNS hostname specification as described in RFC 1034 and RFC 1035. They may include upper- and lower-case Latin characters, Arabic numerals and dashes. They may not include spaces or underscores; dashes should be used instead.
- As of February 2005, language codes in any Wikimedia cloak are no longer allowed. All cloaks will take the form of
project/Username. Name conflicts will be handled on a case-by-case basis.
- As of March 2006, contacts may set cloaks for Wikimedia projects other than Wikipedia. See the list below, and if your project isn't listed, speak to a contact.
Obtaining a cloak 
Cloaks can now be requested. In addition to the freenode staff use for unaffiliated cloaks, our project cloaks are only issued to users who meet the following criteria:
- User must have a verified e-mail address
- User must have at least 250 edits on Wikimedia projects
- User must have a Wikimedia project account registered for at least three months
As part of the cloak request process at the above location, you will be given instructions to prove that your IRC nick and on-wiki username belong to the same person (proof is needed in both directions).
The latter two requirements are designed to prevent abuse of cloaks around freenode. It is hoped that the vast majority of the time they won't prevent genuine contributors from getting cloaks, but in the meantime while waiting to meet these requirements it is pointed out that unaffiliated cloaks can be acquired from freenode staff.
Please note that you will only be contacted by a group contact if there are questions or issues regarding your request. Cloak requests may take up to a week to be processed so please be patient.
Activating your cloak 
Once you get a cloak, you need to identify yourself to NickServ to activate it. Type
/msg nickserv identify <your password> or just put your NickServ password as your server password in your IRC client.
There is normally a few seconds delay between identifying to NickServ and your cloak being set. This can result in the following:
[21:00] » Join: An_IRC_User (~User@22.214.171.124)
[21:00] × Quit: An_IRC_User (~User@126.96.36.199) (Changing host)
[21:00] » Join: An_IRC_User (~User@wikimedia/Example)
This usually happens because the IRC client has been configured to automatically join channels upon a successful connection to the server. Caution is advised when doing this as, in the example above, a cloak is rendered useless because the exposed IP address is displayed before the cloak is set.
Cloak options 
In the past, only Wikipedia cloaks have been offered; these cloaks took the form of wikipedia/Username (your cloak is made of your on-wiki username, not your IRC nickname). Users are now permitted to request a project specific cloak (but not a language-based cloak) using the normal system.
Cloaks may (depending on your preference):
- Have the first letter of your username be upper or lower case
- Be entirely in lower case
- Contain the characters a-z, A-Z, 0-9 and hyphens (-).
Currently permitted cloaks include:
- wikimedia/Username *
- mediawiki/Username **
- * For users who participate in multiple projects or are affiliated with the Foundation.
- ** For MediaWiki developers with commit access.