The complexities of Wi-Fi don't end here. Every country has its own unlicensed spectrum allocation policy. This specifically dictates allowed power levels and allowed users for the spectrum. In the US, for example, the FCC decides this and if you use WLANs in the US you have to abide by these regulations. In some countries, not doing so is a punishable offense.
Now let us look at how we can find the default regulatory settings and then how to change them if required.