Introduction of 40 Gigabit QSFP+ Transceiver

QSFP+ (Quad Small Form-factor Pluggable Plus) transceiver interfaces a network device motherboard (for a switch, router, media converter or similar device) to a fiber optic cable, which is widely used for data communications applications. It is a industry format jointly developed and supported by many network component vendors. QSFP+ is also the IEEE standard connector for the emerging 40GbE standard. QSFP+ modules increase the port-density by nearly 3 times when compared to SFP+ module.

 

Overview on 40G QSFP+ Transceiver

40G QSFP+ transceivers are designed to support Serial Attached SCSI, 40G Ethernet, 20G/40G Infiniband, and other communications standards. The 40G QSFP+ modules are favorable for high density 40G optical network. These modules are designed to operate over single-mode or multimode fiber systems with differently optimized lasers under different standards. 40G QSFP+ transceiver interface can be either duplex LC or 12-fiber MTP/MPO as shown in the following picture. The 40G QSFP+ transceiver module with MTP/MPO interface is a hot-swappable, parallel fiber-optical module with 4 independent 10 gigabit per second data lanes in each direction to provide 40Gbps aggregate bandwidth. 40G QSFP+ modules offer customers a wide variety of high-density 40 gigabit Ethernet connectivity options for data center, high-performance computing networks, enterprise core and distribution layers, and service provider transport applications.

 

Application of Different 40G QSFP+ Transceivers

The transceiver is used primarily in short reach applications in switches, routers, and data center equipment where it provides higher density than SFP+ modules. With the evolving of the format specification, now in the market, you can find a wide varieties of 40G QSFP+ transceivers including the short distance types, Bidi, and long distance types, of which 40GBASE-SR4 (QSFP-40G-SR4), 40GBASE-LR4 (QSFP-40G-LR4) and 40GBASE-ER4 (QSFP-40G-ER4) are the most commonly used physical layers for 40G QSFP+ modules.

 

QSFP-40G-SR4 (short range) transceiver has a port type for multimode fiber and uses 850nm lasers. It supports link lengths of 100 m and 150 m respectively on laser-optimized OM3 and OM4 multimode fiber cables. It is commonly used in data centers to interconnect two Ethernet switches with 12 lane ribbon OM3/OM4 cables. Primarily it enables high-bandwidth 40G optical links over ribbon fiber cables terminated with multi-fiber connectors (MTP/MPO), and could also be used along with ribbon to duplex fiber breakout cables for connectivity to four 10GBASE-SR optical interfaces.

 

QSFP-40G-LR4 (long range)or QSFP-40G-ER4 (extended range) transceiver has a port type for single-mode fiber and uses 1300nm region lasers. It uses two strands of fiber and combines four wavelengths by CWDM technology, delivering serialized data at a rate of 10Gbit/s per wavelength. Thus the optical interface can be simplified to standard LC connectors. QSFP-40G-LR4 transceiver is most commonly deployed between data canters or for IXP (Internet exchange point) site.

 

Conclusion

The QSFP+ transceiver is a great solution for multi-lane data communication and interconnect applications. fiber-mart.COM offers the best 40G QSFP+ modules. All these 40G QSFP+ modules are Cisco, Juniper, IBM and HP compatible. In addition to 40Gbps Ethernet interconnects, it can be used in datacom/telecom switch, and router connections, as well as data aggregation and backplane applications. Also you can have a wide selection of other transceivers and direct attached cables at fiber-mart.COM, including XFP transceivers, SFP transceivers, CFP modules, copper DAC, active optical cable and so on.