in most cases kanang modem router na hatag sa internet provider is preconfigured and is restricted.why do you have to change the ip by the way? if dynamic or automatic ip ang hatag sa dsl is mao na jud na cya.if gusto ka ug static or manual configured ip is lain na pud na cya istoryaha.try lang ug request sa imo provider kon mo ilis ba sila ug manual configured ip.try lang basta mao na ako suggestion nimo...gudluck