Modifies the Rights Identifiers attribute of a given X25 Relay
    Permanent Virtual Circuit instance to include at least the
    specified identifier name or names.
    add  [node  node-id] x25 relay pvc pvc-name -
         rights identifiers {simplename[,simplename...]}
    Rights Identifiers
    Default: No rights identifiers    Value: Set of simple names
    Rights identifiers possessed by this entity. These rights are
    used to access the local PVC and relayed PVC if it resides on
    the local system.