Voip the panasonic kx nt343 system telephone is an ip telephone for the panasonic kxtde telephone system it is designed to be allocated it own ip address and be connected onto a lan if you tried to use the panasonic kx nt343 system telephone on a normal phone extension or telephone line then it will not work 3 line backlit display the lcd display on the panasonic kx nt343 system phone is 3 line backlit display so even in a dimly lit room the screen will be easy to see ful