The type of cPanel license you need and use depends on the type of server that has been set up; virtual or full dedicated. cPanel VPS licenses will ONLY work on servers with virtualization software such as Virtuozzo, Xen, OpenVZ or VMware software installed. Virtualization software sets up different virtual instances within a physical server that you can resell to clients. You will need to have one cPanel VPS license for EACH virtual instance that you setup on you server. There is no difference in features or functionality between a  cPanel dedicated cPanel license and a cPanel VPS license.  All options are exactly the same. With both licenses, as long as the server’s base IP has a cPanel license on it, it will cover unlimited IP’s and unlimited cPanel hosting accounts that are set up on that server.