anchor.diff:      lists:member(Name, CrashedNodes).
   
   %% Is this fault allowed?
  -fault_allowed({call, _Mod, _Fun, _Args}, FaultModelState) ->
  -    Tolerance = 1,
  -    num_active_faults(FaultModelState) < Tolerance.        %% We can tolerate another failure.
  +fault_allowed({call, _Mod, _Fun, _Args}, #fault_model_state{tolerance=Tolerance}=FaultModelState) ->
  +    %% We can tolerate another failure.
  +    num_active_faults(FaultModelState) < Tolerance.        
   
   %% Should we do node debugging?
   fault_debug(Line, Args) ->
  
positive.code: fault_functions(JoinedNodes) ->
      lists:map(fun({call, _Mod, Fun, _Args}) -> Fun end, fault_commands(JoinedNodes)).
  
  fault_initial_state() ->
      CrashedNodes = [],
      SendOmissions = dict:new(),
      ReceiveOmissions = dict:new(),
  
      #fault_model_state{crashed_nodes=CrashedNodes, 
                         send_omissions=SendOmissions,
                         receive_omissions=ReceiveOmissions}.
  %% Receive omission.
  fault_precondition(#fault_model_state{crashed_nodes=CrashedNodes}=FaultModelState, {call, _Mod, begin_receive_omission, [SourceNode, DestinationNode]}=Call) ->
      %% Fault must be allowed at this moment.
  
negative.code: %%% Fault Model
  %%%===================================================================
  
  -record(fault_model_state, {tolerance,
                              crashed_nodes,
                              send_omissions,
                              receive_omissions}).
  
  