Sabu you asked the same question i was going to ask.

4n7hr4x i think you should use user login. what happens when i want to goto a friends house, school, work, ect and switch between dial up and multiple broadband lines i will have multiple ips. also if i have only one ip and then a router and a private ip serving x number of computer(network concepts) what happens if we all want to use this service but do not want to each other to beable to delete pictures. also people may want to make some images private.