unable to connect in LAN
 

Hai all,
I am very new in linux ..just now i had installed the redhat linux 8.0
and connected it in LAN its working fine but suddenly it comes out from the LAN,and now i am unable to connect to the LAN.
please help me out .As i am very new to this so tell me in detail.
Thanx

1. Type "netconfig" at the console anf type in the IP address and gateway and all....
2. come out and next type
service network restart

3. u can see the ipaddress and network info by using the command
ifconfig

hope it helps