``replace-client-id`` must be set to ``true`` and ``duid`` must be used with
``client-id-pop0`` enabled.
+ - ``nas-ports`` (default ``[]``), specifies the NAS port to use in place of
+ a subnet ID (default behavior). It is an array of maps, each map having two
+ elements at most: a port entry (the NAS port value to use) and either a
+ subnet-id entry (the subnet ID to substitute), or a subnet-prefix
+ which is resolved into a subnet and its subnet ID is added, or a
+ shared-network-name which is resolved into a shared-network and its
+ subnets are added. When the subnet-id is 0 or the port is alone,
+ the default substitution is specified i.e. for a subnet ID not in
+ the list this default NAS port value will be used.
+
+- ``realm`` (default ``""``) - is the default realm.
+
- ``reselect-subnet-address`` (default ``false``) - enables subnet reselection
according to the value of the Framed-IP-Address or, respectively,
the Framed-IPv6-Address attribute from the RADIUS access response. With this