It's simple to change the Ip-address..You can reset the modem or switch for a minute and the switch on it..Check the ip-address at
Ip-Details.com if your ip address changed .It's Dynamic ip address ....You can change it many times by resetting the modem...Before changing check your previous ip ,so that you can know the difference.This is will not work if your ip address is a static ip address...Static ip will not change even if you reset the modem.