anchor.diff:               #state{sock=Sock, sock_id=Index, count=Count}=S) ->
       try
           ReqID = <<Index:64/big, Count:64/big>>,
  -        CSumT = convert_csum_req(CSum),
  +        CSumT = convert_csum_req(CSum, Chunk),
           Req = #mpb_writechunkreq{file=File,
                                    offset=Offset,
                                    chunk=Chunk,
  
positive.code:         PK = if PlacementKey == <<>> -> undefined;
                  true                 -> PlacementKey
               end,
          CSumT = convert_csum_req(CSum),
          Req = #mpb_appendchunkreq{placement_key=PK,
                                    prefix=Prefix,
                                    chunk=Chunk,
  
negative.code:             {Res, S#state{count=Count+1}}
      end.
  
  convert_csum_req(none, Chunk) ->
      #mpb_chunkcsum{type='CSUM_TAG_CLIENT_SHA',
                     csum=machi_util:checksum_chunk(Chunk)};
  convert_csum_req({client_sha, CSumBin}, _Chunk) ->
      #mpb_chunkcsum{type='CSUM_TAG_CLIENT_SHA',
                     csum=CSumBin}.
  
  