It is not so much the internet but probably more to do with the settings in the php.ini file. Depending on your host, they may let you modify this.
If you want to find out what your current limits are, create a file... I would call it something like phptest.php.
On that file, take out everything and put this on one line: <?php phpinfo(); ?>
Then upload to your server.... open the browser and and access the file. It will show you what all the settings are.
Typically with larger files, you will need to increase certain limits... these usually include the max file upload size, the max post size, the memory limit, and the max time limit that scripts are allowed to run.
Again, depending on the host, even if they do allow you to alter these settings, they may have terms of service where you would only be allowed to increase them to a point - so be careful.