openstack-manuals/doc/common/section_keystone-concepts.xml
Christian Berendt d90fbeadc5 Removed some duplicate spaces
The duplicate in doc/common/section_getstart_object-storage.xml will
be removed with https://review.openstack.org/#/c/106834/ .

Change-Id: I1f98a479568be9f07a324e60a2dffb9d348f25e4
2014-07-14 21:12:32 +02:00

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XML

<?xml version="1.0" encoding="UTF-8"?>
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version="5.0"
xml:id="keystone-concepts">
<?dbhtml stop-chunking?>
<title>OpenStack Identity concepts</title>
<para>The OpenStack<glossterm>Identity Service</glossterm> performs the
following functions:</para>
<itemizedlist spacing="compact">
<listitem>
<para>Tracking users and their permissions.</para>
</listitem>
<listitem>
<para>Providing a catalog of available services with their API
endpoints.</para>
</listitem>
</itemizedlist>
<para>When installing OpenStack Identity service, you must register
each service in your OpenStack installation. Identity service
can then track which OpenStack services are installed, and
where they are located on the network.</para>
<para>To understand OpenStack Identity, you must understand the
following concepts:</para>
<variablelist>
<varlistentry>
<term>User</term>
<listitem>
<para>Digital representation of a person, system, or
service who uses OpenStack cloud services. The
Identity service validates that incoming requests
are made by the user who claims to be making the
call. Users have a login and may be assigned
tokens to access resources. Users can be directly
assigned to a particular tenant and behave as if
they are contained in that tenant.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Credentials</term>
<listitem>
<para>Data that confirms the user's identity. For
example: user name and password, user name and API
key, or an authentication token provided by the
Identity Service.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Authentication</term>
<listitem>
<para>The process of confirming the identity of a user.
OpenStack Identity confirms an incoming request
by validating a set of credentials supplied by the
user.</para>
<para>These credentials are initially a user name and
password, or a user name and API key. When user
credentials are validated, OpenStack Identity issues an
authentication token which the user provides in subsequent
requests.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Token</term>
<listitem>
<para>An alpha-numeric string of text used to access
OpenStack APIs and resources. A token may be
revoked at any time and is valid for a
finite duration.</para>
<para>While OpenStack Identity supports token-based
authentication in this release, the intention is
to support additional protocols in the future.
Its main purpose is to be an integration service,
and not aspire to be a full-fledged identity store
and management solution.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Tenant</term>
<listitem>
<para>A container used to group or isolate resources.
Tenants also group or isolate identity objects.
Depending on the service operator, a tenant may map
to a customer, account, organization, or project.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Service</term>
<listitem>
<para>An OpenStack service, such as Compute (nova),
Object Storage (swift), or Image Service (glance).
It provides one or more endpoints in which
users can access resources and perform operations.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Endpoint</term>
<listitem>
<para>A network-accessible address where you access a service,
usually a URL address. If you are using an extension for
templates, an endpoint template can be created, which
represents the templates of all the consumable services
that are available across the regions.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Role</term>
<listitem>
<para>A personality with a defined set of user rights and
privileges to perform a specific set of operations.</para>
<para>In the Identity service, a token that is issued
to a user includes the list of roles. Services that are
being called by that user determine how they interpret the
set of roles a user has and to which operations or
resources each role grants access.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Keystone Client</term>
<listitem>
<para>A command line interface for the OpenStack
Identity API. For example, users can run the
<command>keystone service-create</command> and
<command>keystone endpoint-create</command> commands
to register services in their OpenStack
installations.</para>
</listitem>
</varlistentry>
</variablelist>
<para>The following diagram shows the OpenStack Identity process
flow:</para>
<mediaobject>
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