anchor.diff:      message(Dir, Bin, N);
   
   %% incoming request
  -message(recv, <<_:32, 1, _/bits>> = Bin, N) ->
  -    [Bin, 1 < N, fun ?MODULE:message/3, N-1];
  +message(recv, <<_:32, 1:1, _/bits>> = Bin, N) ->
  +    [Bin, N < 16, fun ?MODULE:message/3, N+1];
   
   %% incoming answer
   message(recv, Bin, _) ->
  
positive.code:     [Bin];
  
  %% sent request
  message(ack, <<_:32, 1, _/bits>>, _) ->
      [];
  
  %% sent answer or discarded request
  message(ack, _, N) ->
      [0 =< N, fun ?MODULE:message/3, N+1].
  
  %% ------------------------------------------------------------------------
  
  
negative.code:     LRef = ?util:listen(SN,
                          [T,
                           {sender, SS},
                           {message_cb, ST andalso {?MODULE, message, [0]}}
                           | [{packet, hd(?util:scramble([false, raw]))}
                              || T == sctp andalso CS]],
                          [{capabilities_cb, fun capx/2},
  