Wifi stays connected but wont load websites...

[cilmike2]

I just installed Ubuntu 9.04 on my dell latitude. i have the Intel 3945 wireless adapter. It finds and connects my wireless router fine, and it will bring up web pagers initially, but after about 30 seconds i loose access to the web. i keep my ip address and and all the connection stays the same however i cant load any web pages and i cant download or check to see new updates so i know its not just Firefox. does anyone have any ideas?

[cilmike2]

I wanted to add a little more information... If i reconnect the network connection, it works again for a little bit. i have tried switching to a wep encryption and that did nothing. it seems like the connection forgets the encryption key and can no longer communicate with the router even though it still has the ip address and connection.