Multi-DB config terms

I'm want to install multi-db to add 16 databases, but I'm not quite sure what some of the terms in the db-config.php file mean.

What am I setting here, and what values will I be looking to add?
add_dc_ip('123.123.123.', 'dc1');

What is this table for? What is the table for? (Hints needed for naming)

Do I modify this, and what do I modify?
add_db_server('global', 'dc1', 1, 1,'','',
'wpmu_global', 'db_user_name', 'db_user_name_pass');

How about this? Do I leave it as is?
add_db_server('vip1', 'dc1', 1, 1,'','',
'wpmu_vip_1', 'db_user_name', 'db_user_name_pass');

What is this?
add_vip_blog(1, 'vip1');