The Agilent E1618A 622 Mb/s Optical Line Interface provides OC-12c (SONET STS-12c and SDH STM-4c) access to the system under test via SC optical connectors. The LIF is a singe-mode device that can also be used with multi-mode systems when the appropriate attenuator is fitted. The Agilent E1618A is a component of the Agilent Broadband Series Test System (BSTS).