rsync - what can it do?

[bob parker]

Hi

Maybe I'm barking completely up the wrong tree but here goes.

I've downloaded a 700meg iso by ftp using a steam powered dial up connection.
It took a week and naturally many resumes.

Murphy's Law did not take a holiday of course so the md5sum of the downloaded 
iso does not match the md5sum of the one at the mirror.

Can rsync be used to selectively fetch the part or parts of the iso that are 
in error assuming that the mirror is also an rsync mirror?

How can I tell?

Thanks 

Bob