anchor.diff:  encrypt_and_send_chunk(
     #params{
        socket = Socket, rekey_interval = Seq,
  +     shared_secret = SharedSecret,
        key = Key, iv = {IVSalt, _}, hmac_algorithm = HmacAlgo} = Params,
     Seq, Cleartext) ->
       %%
  
positive.code:                     {Key_1, <<IVSalt:IVSaltLen/binary, IVNo:48>>} =
                          hmac_key_iv(
                            Params#params.hmac_algorithm,
                            Key, R, KeyLen, IVLen),
                      Params#params{iv = {IVSalt, IVNo}, key = Key_1};
                  _ ->
                      error
  
negative.code:     of
          ok ->
              {Key_1, <<IVSalt_1:IVSaltLen/binary, IVNo_1:48>>} =
                  hmac_key_iv(
                    HmacAlgo, SharedSecret, R, KeyLen, IVSaltLen + 6),
              Params_1 = Params#params{key = Key_1, iv = {IVSalt_1, IVNo_1}},
              Result =
                  gen_tcp:send(Socket, encrypt_chunk(Params_1, 0, Cleartext)),
  