QSFP Transceiver – a Hot-pluggable Transceiver With High Density

As a new Multi-Source Agreement (MSA) for high speed applications such as 40G-BASE, QSFP transceiver, which is one kind of 40G transceiver, can provide four channels of data in one pluggable interface. Each channel is capable of transferring data at 10Gbps and supports a total of 40Gbps. Compared with standard SFP+ modules, QSFP transceiver is with higher density and lower cost. It is designed to enable extremely high-density applications with stacked and ganged configurations.

Advantages of QSFP Transceiver

Since the QSFP transceiver integrates four ultra-high capacity, independent fiber transmit and receive channels, its port density is increased and the total system cost is declined. Actually, its port density is of three times higher than the traditional SFP transceiver, enabling the QSFP to be used to replace four standard SFP modules in space that is only 30 percent larger than a single SFP. In addition, the QSFP transceiver can support Ethernet, Fibre Channel, InfiniBand and SONET/SDH standards with data rates up to 5Gb/s per channel. Thus the QSFP platform demonstrates potential for aggregated higher volumes and improved economics realized from several protocols/applications using the same transceiver.

Classifications of QSFP Transceiver

There are various kinds of QSFP transceivers for different distance requirements and fiber types. According to various criteria, QSFP transceivers can be classified into different categories.

  • Classified by Transport Media

Copper, single mode fiber (SMF) and multimode fiber (MMF) are three kinds of transport media used in 40 Gigabit Ethernet. Different QSFP transceivers may adopt different transport media. According to IEEE Ethernet standard, the followings are commonly used 40 Gigabit Ethernet media system:

QSFP-40G-CR4—40 Gigabit Ethernet over four short-range twinaxial copper cables bundled as a single cable.

QSFP-40G-SR4—40 Gigabit Ethernet over four short-range multimode fiber optical cables.

QSFP-40G-LR4—40 Gigabit Ethernet over four wavelengths carried by a single long-distance single mode fiber optical cable.


QSFP transceiver

  • Classified by Connector Type

Different QSFP transceivers may have different connector interfaces. Through various technologies, many kinds of connectors could be applied into 40 Gigabit Ethernet. And the commonly-used are Duplex LC, MPO and MPO/MTP. MPO and MTP are often used interchangeably. For example, the aforesaid QSFP-40G-SR4 and QSFP-40G-LR4 are transceivers with Duplex LC connectors. While the Cisco QSFP-40G-CSR4 is with MPO/MTP connector.

  • Classified by Transmission Distance

According to transmission distance, QSFP transceivers can be divided into short-range QSFP transceiver and long-range QSFP transceiver. QSFP-40GBD-SR is among the various short-range QSFP transceivers. It supports link lengths of 100 meters and 150 meters over laser-optimized OM3 and OM4 multi-mode fibers respectively. As a long-range QSFP transceiver, QSFP-40G-ER4 has a transmission distance of 40 km.

  • Classified by Wavelength

In a QSFP transceiver, the wavelength of each channel can either be of the same or differs from each other. For instance, The wavelengths of Cisco QSFP-40G-SR4 and Cisco QSFP-40G-CSR4 transceivers are 4×850nm. While the four lanes of QSFP-40G-ER4 are 1271nm, 1291nm, 1311nm and 1331nm respectively.

40 Gigabit Ethernet is really a hot topic in recent years. Accordingly, different kinds of QSFP transceivers are springing up all over the world. As a leading optical network products supplier, Fiberstore supports a full range of both direct attach cables and optical transceivers for 40 Gigabit Ethernet.