Ps3 internet connection?

i use a wireless connection on my ps3 and last night i had a 100% signal but i couldnt connect to the internet it wouldnt obtain the ip address i tried everything from turning off my ps3 rebooting my router rebooting my ps3 i did everything. So then i just gave up and turned off my ps3. Then today when i woke up and turned on my ps3 it connected and said i was signed in. does anyone know why this happened??