May I know if you are looking for a hardware-only solution (Like Routers themselves having this feature, but these kind of routers can get expensive) a software solution (this might involve running some server/software on the owner's computer and keeping it running, and making use of it; Though this can probably be simplified using code, but still it is a operational burden) or if you are looking for a low cost hardware package (Like pre-configured custom built Raspberry Pi, but still there is some initial cost associated with it)?