Pausing and Resuming Download

[NetMaster]

Hi,

I created a downloader which works pretty fine.
I would like to implement the possibility to pause and resume the download.
How can I do that? I have been looking around and found that it is possible to do with webrequest add range. I just can't figure out how to deal with with.
I checked the server where I would like to test it and found out that it is possible to do the resume.

To start the download I use Async.


Any help?

Thank you in advance,

Andrea