The Small Form-Factor Pluggable (SFP) Gigabit Ethernet, Single-Fiber is a bidirectional SFP that installs into the Optical Loop Termination (OLT) designed to accept SFPs. The SFP provides a single optical interface to the GigE physical interface. Installed into an appropriate OLT, the SFP provides a Gigabit Ethernet interface to the supporting system.