Connectivity

Hi Guys,

Thank you for this awesome product .

I have an important question:

Assuming my iBook will have a lot of media (photos, videos etc), i want my readers to be able to view and use this media while traveling. That means that my readers doesn't always have an wireless/3G connection. So when creating a iBook and publishing it to the Store, does it contain all media or each media will be downloaded from the server upon request?

If I simplify it, when I download an iBook from the Store to my Ipad, i can fully use it without an active Internet connection?

Do you have restrictions for the iBook size?

Thanks!