RFC 2193 (rfc2193) - Page 3 of 9

IMAP4 Mailbox Referrals

Alternative Format: Original Text Document
< Previous
Next >
RFC 2193                IMAP4 Mailbox Referrals           September 1997


   Example:

      A001 NO [REFERRAL IMAP://user;AUTH=*@SERVER2/REMOTE]Remote Mailbox

   NOTE: user;AUTH=* is specified as required by [RFC-2192] to avoid a
   client falling back to anonymous login.

   Remote mailboxes and their inferiors, that are accessible only via
   referrals SHOULD NOT appear in LIST and LSUB responses issued against
   the user's home server.  They MUST appear in RLIST and RLSUB
   responses issued against the user's home server. Hierarchy referrals,
   in which a client would be required to connect to the remote server
   to issue a LIST to discover the inferiors of a mailbox are not
   addressed in this document.

   For example, if shared mailboxes were only accessible via referrals
   on a remote server, a RLIST "" "#SHARED/%" command would return the
   same response if issued against the user's home server or the remote
   server.

   Note: Mailboxes that are available on the user's home server do not
   need to be available on the remote server.  In addition, there may be
   additional mailboxes available on the remote server, but they will
   not accessible to the client via referrals unless they appear in the
   LIST response to the RLIST command against the user's home server.

   A MAILBOX-REFERRALS capable client will issue the RLIST and RLSUB
   commands in lieu of LIST and LSUB.  The RLIST and RLSUB commands
   behave identically to their LIST and LSUB counterparts, except remote
   mailboxes are returned in addition to local mailboxes in the LIST and
   LSUB responses.  This avoids displaying to a non MAILBOX-REFERRALS
   enabled client inaccessible remote mailboxes.

4.1. SELECT, EXAMINE, DELETE, SUBSCRIBE, UNSUBSCRIBE, STATUS and APPEND
     Referrals

   An IMAP4 server MAY respond to the SELECT, EXAMINE, DELETE,
   SUBSCRIBE, UNSUBSCRIBE, STATUS or APPEND command with one or more
   IMAP mailbox referrals to indicate to the client that the mailbox is
   hosted on a remote server.

   When a client processes an IMAP mailbox referral, it will open a new
   connection or use an existing connection to the remote server so that
   it is able to issue the commands necessary to process the remote
   mailbox.






Gahrns                      Standards Track
< Previous
Next >