---
title: Security identity
slug: '240'
canonical_url: https://docs.coveo.com/en/240/
collection: glossary
source_format: adoc
---
# Security identity
A {doctitle} is a unique entity that can be used to define a [permission](https://docs.coveo.com/en/223/) on a secured [item](https://docs.coveo.com/en/210/).
Thanks to this permission, [authenticated](https://docs.coveo.com/en/2120/) users who are allowed to access this item can see it in its original [repository](https://docs.coveo.com/en/2739/) or in their Coveo search results.
A security identity belongs to a specific [security identity provider](https://docs.coveo.com/en/242/).

A security identity is composed of a name, a type ([user](https://docs.coveo.com/en/250/), [group](https://docs.coveo.com/en/202/), or [virtual group](https://docs.coveo.com/en/252/)), and an optional field called `AdditionalInfo`.

`AdditionalInfo` can be used to enrich a [security identity](https://docs.coveo.com/en/240/) with custom information to make it unique.
For example, if two users have the same name, `AdditionalInfo` lets you specify more information about each user, like their employee ID.

A security identity typically has at least one [relationship](https://docs.coveo.com/en/243/) with another identity of the same security provider (a _child/parent_ relationship) and sometimes with identities from other security providers (an _alias_ relationship).

For more information on [sources that index permissions](https://docs.coveo.com/en/1779#same-users-and-groups-as-in-your-content-system) and how Coveo handles these permissions, see [Coveo management of security identities and item permissions](https://docs.coveo.com/en/1719/).