gigabit ethernet sfp ports operate in full-duplex mode only and are present on the ws-x4013+ts, ws-x4516-10ge and ws-x4013+10ge supervisors, as well as some switching modules. these ports use the 1000base-sx,1000base-lx, cisco coarse wave division multiplexing (cwdm ) sfps,1000base-t sfp, and 1000base-zx sfp. sfp connectors vary with interface type and may use multimode fiber (mmf), single-mode fiber (smf) cable, or copper ethernet cables.