.. _imap-features:

========
Features
========

The Cyrus IMAP (Internet Message Access Protocol) server provides access to personal mail and system-wide bulletin boards through the IMAP protocol. The Cyrus IMAP server is a scalable enterprise mail system designed for use from small to large enterprise environments using technologies based on well-established Open Standards.

A full Cyrus IMAP implementation allows a seamless mail and bulletin board environment to be set up across one or more nodes. It differs from other IMAP server implementations in that it is run on *sealed nodes*, where users are not normally permitted to log in. The mailbox database is stored in parts of the filesystem that are private to the Cyrus IMAP system. All user access to mail is through software using the IMAP, IMAPS, POP3, POP3S, or KPOP protocols.

The private mailbox database design gives the Cyrus IMAP server large advantages in efficiency, scalability, and administratability. Multiple concurrent read/write connections to the same mailbox are permitted. The server supports access control lists on mailboxes and storage quotas on mailbox hierarchies.


The following documents show the full power of each feature that is included with Cyrus IMAP.

Exceptions notwithstanding, most of this documentation does not involve
the :ref:`imap-rfc-support`.

Security and Authentication
---------------------------

.. toctree::
    :maxdepth: 1

    features/authentication-kerberos
    features/authentication-ldap
    features/authentication-sql
    features/access-control
    features/sealed-system

Mailbox Management
------------------

.. toctree::
    :maxdepth: 1

    features/automatic-creation-of-mailboxes
    features/namespaces
    features/virtual-domains
    features/mailbox-annotations
    features/mailbox-distribution

Message Management
------------------

.. toctree::
    :maxdepth: 1

    features/delayed-delete
    features/delayed-expunge
    features/message-annotations
    features/duplicate-message-delivery-suppression
    features/shared-seen-state
    features/server-side-filtering
    features/event-notifications

Storage
-------

.. toctree::
    :maxdepth: 1

    features/mail-spool-partitions
    features/mailbox-metadata-partitions
    features/quota
    features/single-instance-store

Load Management
---------------

.. toctree::
    :maxdepth: 1

    features/server-aggregation
