An IP address (Internet Protocol address) is a unique number that identifies your Virtual Machine (and your web sites) on the Internet. A domain name is associated with the IP address using the DNS service.
Each Virtual Machine is assigned one static IP address. If you need to allocate additional IP addresses to your VM, you can do so in the eApps Portal - select the VM where you wish to add the IP address, and add the IP address in the Upgrade/Downgrade section. Due to the scarcity of IPv4 addresses, the price for adding IP addresses is on a graduated scale. Also, there is a limit of 25 IP addresses per Virtual Machine.
Some applications and processes can use internal IP addresses. There is a modest fee for these addresses.
If you are on a VPS hosting plan using Virtuozzo and the Parallels PBA Control Panel, please contact Sales if you have any questions - https://support.eapps.com/contact/sales