Hi Alexandr

Here i send you test message. Also i send you two different messages, one with .zip file and one with .rar.

I've got your messages, but they went into my junk folder, probably because some of your fellow countrymen have been naughty ;-) But I've made you a safe sender :-)

Actually, here i want to say few things i thought about after i finished coding. I made my class working with uint8_t type - byte arrays. But then i thought it should be working the same way with any int type actually.. And even with any data if we think of it as a simple sequence of bytes. But here i came to the problem: 1. i can replace uint8_t by template class and then use cast in process() method to get data in byte representation: byte *bytes = reinterpet_cast<byte*>(&in_data) and then just deal with byte sequence. 2. or remove vector from member and treat any structure as sequence of bytes. But the thing is - we need checksum for data stored in structure of checksum for structure itself? Because if we take complex structure(something like map<pair<set<int>,pair<int,string> > >) what checksum are we calculating actually?

Well this is a taster of the dilemmas that you will face, both in writing it, and also in defending your decisions to the Bolshy Boosters at any review. But don't worry for now. The tests look pausible, but do not use Boost.Test this is essential for the cross platform testing system. But it's troublesome to set up. Your docs are skeleton-only - all that I expected - and would need to done using Quickbook and full documentation of functions using Doxygen commands in the source like \brief \detail \pre \post \returns ... But it will do fine for now. Paul --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow@hetp.u-net.com