App clients require the app client container (ACC) in order to run correctly. When you launch an app client using the built-in Java Web Start support for the very first time on a given system Java Web Start must download the ACC itself as well as the app client.
Once Java Web Start downloads the ACC from a given server it caches the ACC locally so it does not need to download it again.
We know that the ACC's footprint is very large in v2. We are working to shrink the footprint in v3 but this does not help you in the meantime with v2.
If you once get the ACC downloaded during that first launch then later launches will be much faster. In fact, Java Web Start will cache the app client as well so future launches won't even need to download the client again either...unless of course you deploy a new version of the client.
- Tim
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