two module bays on both switches allow you to upgrade as you go, whether you need gigabit uplink or additional port capacity. each module bay will accept either a copper gigabit ethernet module (1000base-t, netgear model ag711t) or a fiber gigabit ethernet module (1000base-sx, netgear model ag711f) for high-speed connection to a server, to connect fiber and copper networks, or to extend your network backbone with high-speed links.