Number portability (LNP)
The right to keep your phone number when switching carriers within the same location. Ported numbers keep their original NPA-NXX in routing data, which is another reason prefix-based location guesses can be wrong.
The right to keep your phone number when switching carriers within the same location. Ported numbers keep their original NPA-NXX in routing data, which is another reason prefix-based location guesses can be wrong.