LEt's simplify:
I run wireless community network. It is open, meaning, there are no restrictions for users to connect. However, I've set network to recognize registered members from visitors. Registered members get static IP leases, and guest get IP's from the pool.
Network is subnetted, and any registered user may connect in any subnet. Therefore I have to provide static IP for user regardles which subnet he connects to. All I have is users MAC.
Right now, I deal with this using DHCP only, but, it is hard to maintain, not because of one user is able to connect to any subnet, but just because all users are separated in subnets, and each subnet needs separate user administration. My idea was to use User Manager so I can handle all users in one place.
Now I am feced with this problem that User Manager can provide just one IP to one user, regardless which subnet he actually connects in.
In UM you can make use of the IP Pool function. If you give the unregistered users a pool called eg "UnregisteredPool" and the registered users a pool called eg "RegisteredPool", you can simply route accordingly. This way you'll have to have two IP Pools on each highsite/hotspot, with those names (RegisteredPool and UnregisteredPool).
I'm sure you can create a workaround.
Just a question, but isn't it perhaps a better idea to give the registered users a PPPoE Account instead?