nickidenthost

Nickidenthost is a coined term used in online discussions to describe the composite identity string a user presents in certain chat and network protocols. It typically refers to the combination of three elements: a nickname, an ident (user name on the host), and a host (the machine or domain from which the user connects). While not a formal standard, the concept helps explain how users are identified in environments that expose multiple fields.

In practice, the most familiar form is the IRC user mask: nickname!ident@host. The nickname is the display name chosen by the user, the ident is a username from the ident protocol running on the user’s host, and the host is the domain name or IP address of the machine. This mask can be seen by other users or servers in chat networks, though many networks treat the host portion differently for privacy and security reasons.

Usage and privacy considerations are important. Some networks mask or restrict the host portion to protect user privacy, while others may rely on additional authentication methods. The ident field can be a source of information leakage or spoofing if not handled carefully, leading practitioners to depend on proxies, SASL authentication, or other verification mechanisms rather than the ident field alone.

Origin and scope: nickidenthost is primarily a descriptive shorthand used in informal documentation and discussions about IRC and similar systems. It is not a formal protocol name, but a way to refer to the common three-part identity visible in user masks. See also: nickname, ident, host, user mask, IRC.