If you are connected to a network with DHCP, you may do:
#dhclient eth0 (or whatever the alias of your connected adapter is)
#yum install system-config-network-tui
Attention in classroom
If you are connected to a network with DHCP, you may do:
#dhclient eth0 (or whatever the alias of your connected adapter is)
#yum install system-config-network-tui