If you are on a standard Fios account (not business) your IP will change every once and a while (could be once a week, could be once a month).

You can get by this by setting up a dyndns account. The actiontec router has this capability built right into the firmware. This will allow you to go to YOURNAME.gotdns.com and it will always point to your network (free service).

If you suspect your address is changing too often (more than once a day) and you have a d-link router you may want to verify that your D-Link router is running the most recent Verizon firmware. (How to update my D-link firmware?)