I want to install zimbra on my server to retrieve emails from gmail through imap. However my server has limited bandwidth sources. So the question is; if I start retrieving emails from gmail, does zimbra use my server's bandwidth or only the client user bandwidth? I mean does it run on the client side or server side? I know that the application itself runs on server side but what I mean is the email retrieval process.

Is it possible to use zimbra as a browser embedded application alternative to a desktop application? If not is there an alternative way to do that? I think with a java applet it should be possible. What do you think?