Passive ip login

Hi all im new to mikrotik and was wondering if mikrotik can do passive ip login.

i know it can use the mac address as a passive login but can it do passive ip.

the reason i ask is that we have a wireless network connected to a cisco catalyst router.

i wish to be able to put a wirless router in a clients house with a fixed ip and allow them to connect to us with out logging in but still manager there bandwidth.

is passive ip possible?

TIA