How to setup expiring password for Wifi on MTNL modem

My friend has a small shop for food items. To attract his customers he is planing to give them free wifi. So he bought MTNL 1mbps plan. He is using the default MTNL router that comes with the connection. Now he wants a option through which we can setup expiring password to the wifi. Like a customer can use the wifi until he or she is in the cafe. And after a hour the password must get expired on its own and a new password must be applied. How can I find this settings in the router. Like I can add around 10 expiring passwords and share.

Well for that you need a very advance router. You cannot do that on the default one. Like a router that comes with dual band and has multiple SSID support. Here you can do one thing. You can limit the IP in DHCP. For example The router wil only offer IP to 10 users. And other than that no one will be connected. So in this way there will be limited connectivity. And you can also limit the bandwidth usage through QoS setup. Just check whether your router has QoS in it or not.

It is right that you have to go for a very high end router. It wont be possible to get the same on a regular one. There are some high end routers that has option to setup more than one wifi network. You can create a temp or guest network on that with a expiry date or expiry password. Most of the routers will come with a time limit to accept a password and that will get expired after that. But for guest network you need very advance options under QoS which is not possible in regular routers.