anchor.diff:    when ?CHUNK_SIZE =< Size ->
       {Data, Q} = deq_iovec(?CHUNK_SIZE, Front, Size, Rear),
       {Params_1, Seq_1, Result} =
  -        encrypt_and_send_chunk(Params, Seq, [?DATA_CHUNK, Data]),
  +        encrypt_and_send_chunk(
  +          Params, Seq, [?DATA_CHUNK, Data], 1 + ?CHUNK_SIZE),
       if
           Result =:= ok ->
               output_handler_xfer(Params_1, Seq_1, Q);
  
positive.code:                     Data = Front ++ lists:reverse(Rear),
                      {Params_1, Seq_1, Result} =
                          encrypt_and_send_chunk(
                            Params, Seq, [?DATA_CHUNK, Data]),
                      if
                          Result =:= ok ->
                              {Params_1, Seq_1};
  
negative.code: encrypt_chunk(
    #params{
       aead_cipher = AeadCipher,
       iv = {IVSalt, IVNo}, key = Key, tag_len = TagLen},
    Seq, Cleartext, Size) ->
      %%
      ChunkLen = Size + TagLen,
      AAD = <<Seq:32, ChunkLen:32>>,
      IVBin = <<IVSalt/binary, (IVNo + Seq):48>>,
      {Ciphertext, CipherTag} =
  