DHCP reservation is the solution for those situations that require a reserved static ip address but you need the rest to just float. A great example is an office with 4 desktop computers and lots of laptop computers coming and going. In a situation like that trying to use dns to assign by host name will just die. Your best bet, if it is available, is dhcp reservation. In this scenario the host name is not the static component it is the mac address. For this to work you will need a router that can do it but once you have one… you will wonder how you ever worked without it.
This is the best option for scanning to email with floating ip addresses or dhcp assigned ip addresses. Hint… do this if you can for scan to folder and scan to smb.
DHCP RESERVATION ON WINDOWS SERVER
DHCP RESERVATION ON CISCO ROUTER
DHCP RESERVATION ON HOME ROUTER
For those of you in linux environment or who just wants to setup a dhcp server on a regular pc then I recommend OPEN DHCP SERVER