The Cisco® 40GBASE QSFP (Quad Small Form-Factor Pluggable) portfolio offers customers a wide variety of high-density and low-power 40 Gigabit Ethernet connectivity options for data center. high-performance computing 00networks. enterprise core and distribution layers. and service provider applications.Cisco QSFP-40G-SR4-S (S-Class)The S-Class Cisco 40GBASE-SR4-S QSFP module supports link lengths of 100 and 150 meters. respectively. on laser-optimized OM3. and OM4/OM5 multimode fibers. QSFP-40G-SR4-S is aligned to IEEE 40GBASE-SR4 optical specifications which support high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP multifiber female connectors. Because the QSFP-40G-SR4-S does not support 4x10G breakout connectivity. see QSFP-40G-SR4 or QSFP-40G-CSR4 for such applications. QSFP-40G-SR4-S does not support FCoE.Cisco QSFP-40G-SR4The Cisco 40GBASE-SR4 QSFP Modules support link lengths of 100 meters and 150 meters. respectively. on laser-optimized OM3. and OM4/OM5 multimode fibers. It primarily enables high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP multifiber female connectors. It can also be used in a 4x10G breakout mode for interoperability with 10GBASE-SR and SFP-10/25G-CSR-S (in 10G mode) interfaces up to 100 and 150 meters on OM3. and OM4/OM5 fibers. respectively. The worry-free 4x10G mode operation is enabled by the optimization of the transmit and receive optical characteristics of the Cisco QSFP-40G-SR4 to prevent receiver overload or unnecessary triggering of alarm thresholds on the 10GBASE-SR and SFP-10/25G-CSR-S (in 10G mode) receiver. and at the same time is completely interoperable with all standard 40GBASE-SR4 interfaces.The 4x10G connectivity is achieved using an external 12-fiber parallel to 2-fiber duplex breakout cable. which connects the 40GBASE-SR4 module to four 10GBASE-SR optical interfaces. Cisco QSFP-40G-SR4 is optimized to guarantee interoperability with any IEEE 40GBASE-SR4 and in 4x10G mode with the 10GBASE-SR and SFP-10/25G-CSR (in10G mode).Cisco QSFP-40G-SR-BD (40G BiDi)The Cisco QSFP 40-Gbps BiDirectional (BiDi) transceiver (Figure 1) is a pluggable optical transceiver with a duplex LC connector interface for short-reach data communication and interconnect applications using MultiMode Fiber (MMF). The Cisco QSFP 40-Gbps BiDi transceiver offers customers a compelling solution that enables reuse of their existing 10 gigabit duplex MMF infrastructure for migration to 40 Gigabit Ethernet connectivity.The Cisco QSFP 40-Gbps BiDi transceiver supports link lengths of 100 and 150 meters on laser-optimized OM3. and OM4/OM5 multimode fibers. respectively.The Cisco BiDi transceiver complies with the QSFP MSA specification. enabling customers to use it on all QSFP 40-Gbps platforms to achieve high-density 40 Gigabit Ethernet networks.Each Cisco QSFP 40-Gbps BiDi transceiver consists of two 20-Gbps transmit and receive channels in the 832-918 nanometer wavelength range. enabling an aggregated 40-Gbps link over a two-strand multimode fiber connection.