The 40G QSFP (Quad Small Form-factor Pluggable) optical module is designed specifically for high density, high speed, and hot-pluggable applications. It is structured by 4 individual transmit channels and 4 individual receiver channels, each of which enables 10Gbps. The 4 channels can also be combined into a total of 40 Gigabit Ethernet links.
The working process of the 4x10G QSFP+ transceiver is: In the transmit direction, four-channel of 10Gbit/s electric signals are transmitted over the electric interface to the 4-channel VCSEL laser. The electric signals convert to optical signals through the VCSEL laser. Reversely, in the receive direction, the optical signals convert to high-speed electric signals through 4-channel PIN. Fig. 1 shows the working principle of the 4x10G QSFP+ transceiver.
Fig.1 – 4x10G QSFP transceiver working principle
QSFP 40G SR4 optical module enables high-bandwidth 40G optical links over 12-fiber MPO/MTP female connectors at the wavelength of 850nm and supports link lengths of 100m on OM3 and 150m on OM4. It also can be used in a 4x10G breakout mode for interoperability with 10GBASE SR modules. The 4x10G connectivity is achieved using a 12-fiber MTP/MPO parallel to a 2-fiber duplex LC multimode breakout cable, which connects the QSFP SR4 optical transceiver to four SFP+ SR optical modules. Fig. 2 shows how to achieve QSFP-40G-SR4 to 4xSFP-10G-SR connection and required 40G to 4x10G breakout MMF cable.
Similarly, 40G QSFP+ CSR4 optical module also can be used in a 4x10G breakout connectivity with MTP/MPO parallel to duplex LC fiber breakout cables for connectivity to four 10GBASE-SR interfaces. The difference is 40Gb QSFP+ CSR4 extends the length link up to 400m over OM4 multimode cable.
Fig.2 – QSFP 40G SR4 to 4x10G SFP+ SR connection with MTP female to 4 LC Duplex multimode breakout cable
QSFP 40G LR optical transceiver supports 10km transmission distance over Single-mode Fiber (SMF), which enables 40G data rates over 12-fiber parallel fiber with MPO/MTP multifiber connectors. 40G QSFP LR transceiver can also be used in a 4x10G connectivity to fulfill interoperability with 10G SFP+ LR transceivers. The 4x10G connectivity is achieved by using a 12-fiber MTP Female to a 2-fiber single-mode duplex breakout cable, which connects the QSFP 40G LR module to four 10GBASE-LR optical ports. Fig. 3 shows how to achieve QSFP 40G LR to 4x10G SFP+ LR connection and the required 40G to 4x10G SMF breakout cable.
Fig.3 – QSFP 40G LR to 40x10G SFP+ LR connection with MTP female to 4 LC duplex single-mode breakout cable
The answer is no. The reason you will know by learning the working process illustrated next of 40G QSFP+ LR transceivers. QSFP 40G LR4 module adopts CWDM (Coarse Wavelength Division Multiplexing) technology. It supports the link up to 10km over a pair of SMF with duplex LC connectors. In the transmit direction, 4x10Gbe serial digital signal transmit to DML laser with four wavelengths of 1271nm, 1291nm, 1311nm, and 1331nm. Then 4 CWDM optical signals are multiplexed to a single-mode fiber over an LC connector. In the receive direction, 40G CWDM optical signals input and demultiplex into 4 individual 10G optical data streams with different wavelengths, as shown in Fig. 4. QSFP ER4 works similarly to QSFP LR4. Fig. 4 shows the working principle of the QSFP+ LR4 transceiver. By learning the working process of QSFP-40G-LR4 and QSFP-40G-ER4, understandably, they can't be split into 4 individual duplex SMF fiber to achieve 4x10G connectivity with duplex LC connector structure.
Fig.4 – QSFP+ LR4 and ER4 transceivers working principle
From the above discussion, we learn the working principle of QSFP 4x10G transceivers and 4x10G connectivity supported 40G QSFP+ transceivers types are QSFP-40G-SR4, QSFP-40G-CSR4, QSFP-40G-LR, which are structured with MTP/MPO connectors in common. As a low power consumption, high density, and cost-effective solution for 10G to 40G migration, QSFP 4x10G transceivers have been widely applied in data center interconnection, especially for short-distance high-speed transmission.
has been focusing on the R&D and production of high-speed optical interconnect products for 10 years. QSFP 4x10G transceivers and supported MTP/MPO to LC breakout cables are available at the best price. Contact us and get a quote.
