anchor.diff:                {'Origin-Host',  OH},
                 {'Origin-Realm', OR}]).
   
  +%% prepare_retransmit/3
  +
  +prepare_retransmit(Pkt, ?CLIENT, {_, _}) ->
  +    #diameter_packet{header = #diameter_header{is_retransmitted = true}}
  +        = Pkt,
  +    {send, Pkt}.
  +
   %% handle_answer/4
   
   handle_answer(Pkt, _Req, ?CLIENT, _Peer) ->
  
positive.code:                                   {peer_up = false,
                                     peer_down = false,
                                     handle_error = false,
                                     prepare_retransmit = false,
                                     default = ?MODULE}},
                          {answer_errors, callback}]}]).
  
  
negative.code: %% diameter callbacks
  -export([pick_peer/4,
           prepare_request/3,
           prepare_retransmit/3,
           handle_answer/4,
           handle_request/3]).
  
  