> > Also how could wireless link change data inside of a TCP packet ? > > Then checksum should become wrong and the packet rejected ... ? > > what you are solving. If your problem is that the TCP transmission > completes successfully (i.e. everything's OK as far as TCP is concerned) > but the data that came out of the pipe is different that the data that > had been sent, that should be a different problem. exactly - succesfull completion but invalid data. > > to compare stored data with packet contents (with 100MB ftp file > > it will be a lot of fun :-( ) > > Can you produce a "binary diff" of sent and received file to see how > exactly they differ? Are the two files completely different? Or do > they differ just in a couple of places? Is something missing? Is > something changed? If so, how? That's how I managed to isolate some > difficult data-dependent bugs, it might be useful here, too. I did (I wrote program for it). 16MB are totaly dirrerent (from offset 14MB aligned on page boundary) and some other part (10kB) is shifted by 1 byte. That part is not even 512B aligned. This is list of different parts between 148005111 long files f1 and f2: from 14557184, cnt 4481067 from 19038287, cnt 11393 at 19038288 (by 1) in f1 at 19038286 (by -1) in f2 from 19049716, cnt 1162 at 19049717 (by 1) in f1 at 19049715 (by -1) in f2 from 19050914, cnt 46210654 from 68514564, cnt 4855808 at 68518659 (by 4095) in f2 "at" block is where the block was found in other file. devik