In a small lan, you have to set static IP for devices as network printers, to assure that all clients will find devices on the fixed port IP settings.

Some router has the capability to assign allways the same IP to a specific MAC address.

If your router cannot do this, assign to the printer a static IP, possibly outside the range managed by the router DHCP, and generate client's TCP/IP port on this IP.

 

About your doubt regarding the purpose of the DHCP option, imagine a wide ambient, with several buildings and/or floors, multiple servers and a lot of printers, with the possibility to have some of them faulted and sent by the internal service to repair, and some spare installed on the fly to replace the faulted one, without having to reconfigure the printer.

Remember that a real DHCP server (not the limited ones embedded in a router), if correctly programmed, can reserve a specific and fixed IP to a specific device.

So, if you move your printer from a location to another (with different subnet) the printer is automatically set from the local DHCP to the right local "fixed" IP address reserved for the printer in that location, and all users are immediatly able to print.

 

Regards

 

GandalfWiz