+.B timeout [<op>=]<val> [...]
+This directive allows to set per-operation timeouts.
+Operations can be
+
+\fB<op> ::= bind, add, delete, modrdn, modify, compare\fP
+
+The \fBsearch\fP operation is already controlled either
+by the \fBtimelimit\fP parameter or by server-side enforced
+time limits (see \fBtimelimit\fP and \fBlimits\fP in
+.BR slapd.conf (5)
+for details).
+Timeout is meaningless for the remaining operations,
+\fBunbind\fP and \fBabandon\fP, which do not imply any response,
+while it is not yet implemented in currently supported \fBextended\fP
+operations.
+If no operation is specified, the timeout \fBval\fP affects all
+supported operations.
+
+Note: if the timelimit is exceeded, the operation is cancelled
+(according to the \fBcancel\fP directive);
+the protocol does not provide any means to rollback operations,
+so the client will not be notified about the result of the operation,
+which may eventually succeeded or not.
+In case the timeout is exceeded during a bind operation, the connection
+is destroyed, according to RFC4511.
+
+Note: in some cases, this backend may issue binds prior
+to other operations (e.g. to bind anonymously or with some prescribed
+identity according to the \fBidassert-bind\fP directive).
+In this case, the timeout of the operation that resulted in the bind
+is used.
+
+.TP
+.B tls {[try-]start|[try-]propagate}
+execute the StartTLS extended operation when the connection is initialized;
+only works if the URI directive protocol scheme is not \fBldaps://\fP.
+\fBpropagate\fP issues the StartTLS operation only if the original
+connection did.
+The \fBtry-\fP prefix instructs the proxy to continue operations
+if the StartTLS operation failed; its use is \fBnot\fP recommended.
+
+.SH BACKWARD COMPATIBILITY
+The LDAP backend has been heavily reworked between releases 2.2 and 2.3,
+and subsequently between 2.3 and 2.4.
+As a side-effect, some of the traditional directives have been
+deprecated and should be no longer used, as they might disappear
+in future releases.
+
+.TP
+.B acl-authcDN "<administrative DN for access control purposes>"
+Formerly known as the
+.BR binddn ,
+it is the DN that is used to query the target server for acl checking;
+it is supposed to have read access on the target server to attributes used
+on the proxy for acl checking.
+There is no risk of giving away such values; they are only used to
+check permissions.
+
+.B The acl-authcDN identity is by no means implicitly used by the proxy
+.B when the client connects anonymously.
+The
+.B idassert-*
+feature can be used (at own risk) for that purpose instead.
+
+This directive is obsoleted by the
+.B binddn
+arg of
+.B acl-bind
+when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.
+
+.TP
+.B acl-passwd <password>
+Formerly known as the
+.BR bindpw ,
+it is the password used with the above
+.B acl-authcDN
+directive.
+This directive is obsoleted by the
+.B credentials
+arg of
+.B acl-bind
+when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.
+
+.TP
+.B idassert-authcDN "<administrative DN for proxyAuthz purposes>"
+DN which is used to propagate the client's identity to the target
+by means of the proxyAuthz control when the client does not
+belong to the DIT fragment that is being proxied by back-ldap.
+This directive is obsoleted by the
+.B binddn
+arg of
+.BR idassert-bind
+when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.
+
+.TP
+.B idassert-passwd <password>
+Password used with the
+.B idassert-authcDN
+above.
+This directive is obsoleted by the
+.B crendentials
+arg of
+.B idassert-bind
+when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.
+
+.TP
+.B idassert-mode <mode> [<flags>]
+defines what type of
+.I identity assertion
+is used.
+This directive is obsoleted by the
+.B mode
+arg of
+.BR idassert-bind ,
+and will be dismissed in the future.
+
+.TP
+.B idassert-method <method> [<saslargs>]
+This directive is obsoleted by the
+.B bindmethod
+arg of
+.BR idassert-bind ,
+and will be dismissed in the future.
+
+.TP
+.B port <port>
+this directive is no longer supported. Use the
+.B uri
+directive as described above.
+
+.TP
+.B server <hostname[:port]>
+this directive is no longer supported. Use the
+.B uri
+directive as described above.
+
+.TP
+.B suffixmassage, map, rewrite*
+These directives are no longer supported by back-ldap; their
+functionality is now delegated to the
+.B rwm
+overlay. Essentially, add a statement
+
+.B overlay rwm
+
+first, and prefix all rewrite/map statements with
+.B rwm-
+to obtain the original behavior.
+See
+.BR slapo-rwm (5)
+for details.
+.\" However, to ease update from existing configurations, back-ldap still
+.\" recognizes them and automatically instantiates the
+.\" .B rwm
+.\" overlay if available and not instantiated yet.
+.\" This behavior may change in the future.
+
+.SH ACCESS CONTROL
+The
+.B ldap
+backend does not honor all ACL semantics as described in
+.BR slapd.access (5).
+In general, access checking is delegated to the remote server(s).
+Only
+.B read (=r)
+access to the
+.B entry
+pseudo-attribute and to the other attribute values of the entries
+returned by the
+.B search
+operation is honored, which is performed by the frontend.
+
+.SH OVERLAYS
+The LDAP backend provides basic proxying functionalities to many overlays.
+The
+.B chain
+overlay, described in
+.BR slapo\-chain (5),
+and the
+.B translucent
+overlay, described in
+.BR slapo\-translucent (5),
+deserve a special mention.
+
+Conversely, there are many overlays that are best used in conjunction
+with the LDAP backend.
+The
+.B proxycache
+overlay allows caching of LDAP search requests (queries)
+in a local database.
+See
+.BR slapo\-pcache (5)
+for details.
+The
+.B rwm
+overlay provides DN rewrite and attribute/objectClass mapping
+capabilities to the underlying database.
+See
+.BR slapo\-rwm (5)
+for details.
+