anchor.diff:              %State1 = locally_disable_lease(State, NewLease),
               {ok, State, SlideOp};
           {split, fail, _Lease} ->
  -            %% log:log("prepare_send_delta2: split failed~n", []),
  +            log:log("prepare_send_delta2: split failed~n", []),
               {abort, {protocol_error, Msg}, State, SlideOp}
       end.
   
  
positive.code: -spec prepare_send_delta1(State::dht_node_state:state(), SlideOp::slide_op:slide_op(),
                            ReplyPid::comm:erl_local_pid())
          -> {ok, dht_node_state:state(), slide_op:slide_op()} |
             {abort, Reason::unkown_lease, State::dht_node_state:state(), SlideOp1::slide_op:slide_op()}.
  prepare_send_delta1(State, OldSlideOp, ReplyPid) ->
      % start to split own range
      %log:log("prepare_send_delta1 ~p~n", [slide_op:get_type(OldSlideOp)]),
  
negative.code:             log:log("unknown lease in prepare_send_delta1~n"),
              log:log("~p:~p~n", [ActiveLease, PassiveLeaseList]),
              log:log("~p~n", [Interval]),
              {abort, {protocol_error, unknown_lease_in_prepare_send_delta}, State, OldSlideOp}
      end.
  
  
  -spec prepare_send_delta2(State::dht_node_state:state(), SlideOp::slide_op:slide_op(),
                            EmbeddedMsg::any())
          -> {ok, dht_node_state:state(), slide_op:slide_op()} |
             {abort, Reason::{protocol_error, EmbeddedMsg::any()}, State::dht_node_state:state(), SlideOp1::slide_op:slide_op()}.
  prepare_send_delta2(State, SlideOp, Msg) ->
      % check that split has been done
  