your router may have been attacked by a smurf attack. get into the router by typing
192.168.0.1 or
192.168.1.1
user name is admin , no pass needed
look in the log section
it will probably show smurff.
google for smurf and read about how smurf can cripple whole countries.
you can rectify this by useing a paper clip ans in a small hole on the back of the router, do a factory reset.
i got hit last night. i've got the wired internet back, but the wireless access is riuned. its all set right, but our laptops can not access it.
this is the 2nd time in 2 months for me. i'll probably need a new router toady.