I think you must give more information if you want that someone know your problem.
First, try this to know the name of your NIC.
Next, check if the driver used by your NIC is loaded. Try this
If you find "b44" that is the default driver of your Linux for the broadcom card.
And next, check if your NIC is up, try :
If you have nor eth0 or eth1, try to set up your NIC, try :
ifup -v eth0
If you have no error. Check if your DHCP server is ready, try this :